I tried playing in flip-flops once. Reached cross table for a ball, slipped and sacked it right on the metal casting for the corner pocket (with my stick hitting a ball and fouling at the same time, effectively costing me the rack and $20). I was very close to buying a house stick and smashing it into pieces. Now, shoe traction is a must, and a big consideration for me. I only wear the Vans when I'm playing pool. Oddly enough, I skate but I don't wear this pair of Vans. I wear the old-school low tops.
I'm also kind of a woman when it comes to shoes. Between my skate shoes, golf shoes, running shoes, work shoes, and casual shoes, I own over 20 pairs.