I have had a good report with quite a few owners, managers and providers at quite a nimber of Korean spas, here in Philly, now and over the past years. Had lunch or dinner back in the kitchen at all of them many times, and have never seen anyone but me hanging out, unless another customer or repair guy was invited to stay to eat too. I really don't think any muscle is hiding out anywhere inside the shops or sitting outside. I have had to provide the muscle a couple of times to stop a few bad situations. Maybe I'm the guy hiding out, lol.
Now we all know several Chinese spas where Papasan runs the show at the front desk with some of his friends hanging out there. These places are not hiding their protection.