First of all, I’m not French, so take what I say with a grain of salt. My wife however is, and we’ve talked about this a lot aha. But no, I’d never be offended unless it was used in a way to belittle me, which has never happened. Both of us agree that continuing to use ‘vous’ with someone you know creates a certain barrier, even a statement if you will. In most situations, if you start to use tu with, for example a salesman/woman, they will reciprocate. It’s kinda like as the customer, you’ve told them that you don’t expect to be treated so formally and that you’re more comfortable speaking as equals.

I have a great example of this, actually. My wife’s parents are quite annoyed that their two daughters in law continue to use vous with them. We think they do it for a couple of reasons. My wife’s parents are very Catholic, and all 3 of their children (and their spouses) are quite the opposite. It’s almost as if they continue to use vous just to spite them for being so traditional. They also aren’t married, tying into the theme. What’s strange is my father in law has even said to them to use tu, and they refuse. In contrast, I think I started using tu after the second or third time of meeting them, because for me it’s unnatural to speak so formally with people you consider family, and my father in law told my wife (then girlfriend) that it changed our (his and mine’s) relationship completely (for the better of course.)

Anyways, as for Switzerland, I’m not sure. The Romands in the Geneva area tend to be a little more formal than the Savoyards in the bordering areas, but other than that I don’t really know. This subject fascinates me so I’d love to know myself!

I’m in my 30s, and haven’t lived here in France my whole life, but in general, yes. The only times I’ve been addressed with tu in a transactional situation was if either a) I knew the person, or b) in a very informal setting, like ordering a beer at a show that was in some farmers’ field.

Only in Quebec would a cashier use ‘tu’ with a customer so freely… It’s actually refreshing compared to the formality of everyday interactions in European francophone countries!