They most definitely do not wear Bluetooth earpieces all day. There was a brief period years ago when it was (relatively) a lot more common, but the richly-deserved backlash appears to have mostly eliminated the practice. I can't even think of the last time I encountered someone who just kept it on all the time. Purely anecdotal, but I think I've actually seen people using phone holsters more recently than I've seen anyone walk around with a Bluetooth earpiece when they weren't actively talking on the phone or driving.

Maybe it's regional, I dunno. I'm in the Bay Area FWIW.