Sorry, but you don't cut someone's tie off like you own the dang thing. Ooh, you're going to give them a free desert for it. Ok, I don't think a $5 cup of ice cream makes up for what is likely a $100 tie. You have no idea how much someone paid for that tie, nor if it was a sentimental piece of clothing someone got from a departed loved one. If you want to keep the place casual, you have a dress code. You don't vandalize and ruin someone's clothes when they walk in, you just turn them away like the other places that won't let you in without a suit and tie. Now, I personally hate dressing up and I don't think ANYONE looks good in those getups, but I would never do what that waitress/hostess did to them.
Review of Dinner at Eight
