This seems to be spinning OT but I'll just add my 2 cents for good measure.
In terms of the "When in Rome..." thing I absolutely feel cultural sensitivity is very important. In my view if I visit someplace else, I need to be appropriate to THAT place and that culture, not by my own standards. It shows respect. Doesn't matter if I personally agree or not.. if I'm there for whatever reason I think it's important to do that. I mean how many people do you hear jumping up and down about how when foreigners immigrate to Australia they should "become aussie" and integrate into society and accept our norms? Seems hypocritical to want that, but then to go barging into another country which accepts a certain code of conduct and not do the same. For me, it's like if I visit a place, church or home or whatever where it's expected to remove one's shoes before entering, then I will. Manners and respect. Now, if I'm in a private place like a hotel room, private area where it's understood more lax conditions are OK then sure. And of course in a hotel room well all bets are off (lol).
Now to John's comments about manners and common courtesy - yes, imho as a grumpy cat middle aged guy (sigh) I see it more and more and it depresses me for the future. Nothing annoys me more, specially as someone who walks a lot for exercise, to have pathway hogs that are not polite enough to move aside or thoughtfful enough to make sure they're NOT using all the space. I understand a group will want to walk together to chat and whatever.. fine, but have some *consideration* for others is all I ask.
I do think we need to be careful to not generalise too much as for as manypath hoggers and feet on bulkhead types out there there are many, young and old, who do have polite manners and perhaps I notice it more when (yes I'll generalise here a younger person) I see it displayed. I try to make a point to acknowledge and thank the person if it directly affects me.. good manners and courtesy should be encouraged but not in an overbearing way or anything.
Back to the QC... I was somewhat amazed when at the food counter yesterday and I picked up tongs to grab some cheese (or at least attempt to LOL) the lady next to me said "Oh it's so hard... Just use your hands.. I did!" uh...... and trust me, I've made an embarassing effort at an unnamed QC in the system once of accidently dropping some salami into the cheese bowl as it slipped out of the damn tongs.. I was mortified but I still try and do the right thing!! Said lady did show some manners in offering to give me some tomato though
However I then noticed one of the staff filling up the bread with their bare hands so..... it was not a great day in that respect...