Its happened to me a lot, where the customers would come from a certain direction then get stuck on a prop or entity and just stand there, Other times, NPC's will walk into the customers and then they wont be able to get to you, but most of the time, the customers start jumping out of the way and then they get to the shop. Its such a hassle that the waiting timer doesn't start until they get inside the shop and so ive had to randomly choose a weapon and keep going back n forth to give it to them.