I've been meaning to expand on this a bit, so here goes.
Legally
No laws were broken as described. Move along.
Public Impressions
Obviously this varies from location to location. Personally I wish the culture in some locations wasn't so paranoid at the mere sight of a firearm. I wish that large portions of the population hadn't bought into the concept of irrationally blaming an item, rather than using two brain cells to figure out what should be obvious. Just imagine the commotion the next time a young, foreign born male is going to cause when purchasing a pressure cooker! Sheer stupidity.
If I'm OCing and someone calls the police, it's still silly, but at least it's worth the hassle IMHO. Getting the police called on you for showing it to friend is also silly, but not worth the hassle IMHO. Besides, if you still have it in hand you can expect a more aggressive response from the police since they don't know what you are doing of it it's loaded, etc.
You don't have to walk around on tip toes, but just use some discretion. Consider how other perceive your actions.
Gun Etiquette
This is the primary issue IMHO. First, let's discuss briefly what gun etiquette is:
http://www.thefreedictionary.com/etiquette
etiquette [ˈɛtɪˌkɛt ˌɛtɪˈkɛt]
n
1. (Sociology) the customs or rules governing behaviour regarded as correct or acceptable in social or official life
2. (Sociology) a conventional but unwritten code of practice followed by members of any of certain professions or groups
The first definition is really covered by the Public Impression above, but the second is what I intend to discuss now. Let's assume for the discussion that you didn't break any of the written rules of gun safety (loaded, finger, barrel, target), yet you still ran afoul of a conventional but unwritten practice about handling firearms.
Most things (particularly dangerous things) or groups have such unwritten rules and their unwritten for a reason. Namely, it's not black and white...although some people will try and make such a rule. Reality isn't so cut and dry so making hard and fast rules doesn't work. Inquire enough of someone who has tried to make a hard and fast rule out of a etiquette and you'll practically always find that what they have really isn't hard and fast at all...it's just as subjective as the etiquette was, but it makes them feel better that they have a rule to follow.
We had one such discussion over alcohol and firearms recently; the reality is that even the glass of water I'm drinking affects my body and judgement, so drawing an arbitrary line at alcohol is an attempt to make a rule out of the general etiquette: don't mess with certain dangerous things while impaired. Am I impaired because I have indigestion? Seasonal allergies or took Benadryl to counter them? Dehydrated? Let's say I've had a beer with dinner and then a threat breaks into my home. Should I not use my HD firearms merely because I've had a beer? Making hard and fast rules don't work for most of life situations, so etiquette, with all of it's vagaries, and personal responsibility/judgement become the "rules."
Another example of this (relevant to your etiquette issue) is the unnecessary (IMHO) handling of loaded firearms in war zones. This is an example of rules being made by those who don't understand the cultural etiquette. Everywhere you go there are clearing barrels because most facilities don't allow loaded firearms in them. So let's get this right, you are required to have a loaded firearm on your person while outside (even within the compound), but step inside a building and suddenly you can't be trusted? Great idea, let's just have everyone handle their loaded firearm at the entrance (you know where there are lots of people) and clear it (obviously reload too). Guess what happens? Mistakes happen and not just into the clearing barrel! Leave the handgun in the holster and treat it like a loaded gun just like you did outside because there is no reason to be handling that loaded firearm. Personally, if you can't trust the person to leave the firearm holstered and secured on their person while inside, perhaps they should have one outside either? Just a thought.*
This is the etiquette you broke and since it's etiquette there is going to be some grey area based on how people interpret things. There is nothing illegal about showing your friend the firearm. Honestly, there shouldn't be a problem with it in public anywhere, but in some places there are problems (use discretion). However, handling a loaded firearm just to show it off is always questionable. I've been asked be some people to show them my Glock and often have refused, even in the privacy of my own home. Sometimes it's just not appropriate due to the people, number of people, purpose of the event, etc., but more generally it's just not necessary. While I don't intent to break any of the written rules, accidents do happen. In general I'd much rather go get a unloaded Glock of the same model from the safe to show than to unload the one I'm carrying.
If that still isn't quite clear, replace Glock/firearm with chainsaw. While there isn't nothing illegal about showing a chainsaw off for your friends and it shouldn't get the police called on you (although people are pretty stupid so it might if you did it in a parking lot), common sense/etiquette say bringing a chainsaw (potentially dangerous) out in a group of people probably isn't the best idea. Furthermore, starting that chainsaw (logically equivalent to unloading/loading a firearm) is even worse of an idea. Depending on the circumstances you might refuse or might take a few people who want to see it aside at an appropriate time and then show the chainsaw off.
Edit: * Obviously storage is different and a good reason to properly unload a firearm. However, at the entrance probably isn't the best location and that's not the intent of the rule.