OP here. As a clarification, I knew nothing about Five Guys except the hype about being great burgers. They are in an upscale eating area, next to Tucanos Brazilian Grill, across the street from PF Chang's, and around the corner from Bar Louie. All rather upscale chains. So, my EXPECTATION was something more akin to a Red Robin, not Steak n' Shake. My problem for not exploring more before trying, but not a big deal. Try something, don't like it, don't go back. Simple.
As far as being fast food, we waited 15 minutes, so not fast.
As others have mentioned, we usually go to local places, and this just re-enforced that for future picks.