I've never been a earbud guy while in a public place, I just feel uncomfortable and uneasy not knowing what's going on around me. Even in the gym, I don't trust others with heavy objects so I want to be onto it.
I get what Tim is saying with the earbud thing making people closed off to everyone else, but I don't really see a problem with it in the grocery store. I do just wish people were more responsive and less oblivious, but people are fucking oblivious without anything in their ears so I guess it makes no difference. I'm not going to the grocery store to talk to people. We have self serve checkouts here which I love because the small talk from the checkout chick can get excruciating for me.
The whole, 'how are you?' 'got much planned for the rest of the day?' talk I just don't understand. I know they are being polite and have to have good customer service but it's so fake and awkward and there is simply no end result. Unless you become a regular and know the staff over time, fair enough but one off shit where I'm never going to see them again is just painful.