Personally, when i arrived in the usa 8 years ago i was surprised that people eat dinner at 5:00 pm. In India,where i am from this time was meant for some light snacks and coffee/tea. So you get some light food to fuel you till you have dinner much later.

It's more of a cultural thing and no single thing is good or bad.

Are these people without jobs that eat dinner at 5pm? Most people I know are still at work at 5pm.

Many people seem to snack in the office around 5.