Hey, @improv.
I think it's awesome that your three year old knows how to say it and use it. I also think it's awesome that he actually tries (and succeeds) to create the context for it, too. Smart cookie. :)
re: my pleasure
Well, that's disappointing. Maybe it just doesn't pack the punch we think it should.
re: bud
I think in my case it has to do with the fact that the majority of the people who use it on me are perfect strangers. Male gas station attendants tend to be the ones who do this the most. Women tend to go the sweetie route, which is bizarre, since I can see grandmother's doing it to their younger grandchildren.
re: Thank you
I'm okay with that one, if there's a reason for them to thank me back. If there's not a reason, then not so much. I don't think that happens as nearly as often as these others. I guess I need to do more to see if I can solicit the response. :)
re: acknowledged
Yeah. I was trying to say that it's okay in some cases. It just kind of comes off awkward or abrupt, like I've embarrassed them by saying thank you. I suppose it's their way of being modest.
re: Of course
It's mostly the way it's said. I tried to describe it above but I'd probably need to record someone saying it for full effect.