They seem particularly likely to fall prey to the Flash disease, which means their sites are useless to folks on smartphones. They also routinely miss basic shit like keeping a phone number on every page, especially the menu — don’t make a customer look for it!
All-PDF menu sites are nearly as bad, since they’re nearly impossible to reformat for small devices (again, think about your smartphone use cases!). At the same time, though, keeping a PDF download of your menu in a handy header link is a great idea not used nearly often enough — for a frequently-called neighborhood joint, having to wade through a flash menu every time is just ridiculous.