This game is pretty difficult! After a few tries I found that even with the movement speed I couldn't balance the boxes and the queue and lost a few minutes in.
I love that the customers dash randomly and some times jump into the way, I thought that was hilarious XD
I think this game is great and quite fun.
If I can make a few recommendations, I would say to add just a few tiles for the outside, it would make it feel more like a store imo. could just be a sidewalk tile, and a dark grey/black object representing the road/parking lot. And more importantly some balance needs to be done, because I feel like it becomes impossible to survive after just a few minutes pass.
Nice job!