If my retail experience is any indication, acknowledging customers in this situation is a bad idea. Before you know it, the conversation turns to “I just need one thing!” Or “I promise I’ll be really quick!” and you have to become the asshole to tell them no… Even though the store hours are clearly listed on the front door.
Or if you agree even once, the conversation could easily become “but you did it for me/my friend last time!”
I’ve literally had people sneak into the store using an exit, then act all indignant because I tell them to leave. You give some of these fuckers an inch, they’ll take a mile.