Quote from “the perfect couple” (have not seen yet, but many ads) where Nicole Kidman says “anyone who wears flipflops outside the confines of their own house should be arrested” - there is a time and place where there is an exception. Otherwise other footwear is probably better. From personal experience, a first date at a nice bar/restaurant is not one of them. Neither is the second date. Also unacceptable is forgetting your wallet. If you would wear it to the gym shower- don’t on a date.