(kramer_vs_kramer) - I haven't met any of your store coworkers, and I'm guessing neither have the majority of the people here. So I'd suggest maybe changing the names to protect the innocent, and just concentrate on making strips about the store that are funny without having background information on all the people. Because some of them, like this one, are pretty good.
[Click to view comic: 'Bobby's Lunchtime Bedlam']
It's just offputting having everyone state their name before saying anything.
There's definitely mileage in retail jokes though.