It's a restaurant with a bar, not really a diner. It's more of a place that middle-class workers would go after work to have a few drinks and eat cheaply sourced food. It also doubled as a place for families to go during the day. We have several of these kinds of restaurant chains that all serve microwaved food and have a bunch of memorabilia on the walls. TGI Friday's, Applebee's, Chili's, Fudrucker's, etc.

The original was Max & Erma's. They were the first "casual dining" restaurant that appealed to baby boomer nostalgia in their design/layout. Imagine the bar from Cheer's but with antiques, collectables, and vintage signage all over the walls. It became a chain and was so successful everyone started copying it.