I have a sign like that on my table, to please have design choice picked out before taking a seat. I also added, "we may need to serve the next in line until you've picked out your design. Thank you!" I can see a difference, but I still get a few here and there that don't know what they want, so I'll wait a second or two, but if they don't make up their mind... I ask them to hop down and that I'll work on painting the next person until they decide. Usually either them or their parent will make an immediate decision, but a few times I paint the next in line.
It is crazy when you think about how long they've been in line!

Maybe we give them too many choices.
