As a cashier myself, this is so true. I say no problem all the time, and no one else has a problem. You sound just as nice when you say "no problem" vs. "youre welcome" ; Agreed, I say "No problem" to people all the time.
It's not because of selfies. Me taking quick photos of myself is a lot better than judging an entire generation for taking quick photos of themselves as if people didn't pose for hours per portrait years ago.
I'm bi and just because I like both genders doesn't mean that I can't have a valid relationship or my sexuality isn't "real" and if anyone try's to tell you that it's wrong to be LGBT+ they're the confused one