I know exactly what you mean! I have several pairs of Nikes for indoor and they are all fine, but I got a pair of Nike Zoom Agility in a fun mint color for summer that I have been wearing out and about and I noticed when in stores/restaurants etc they are so slippery... It's like there is a layer of oil all over the floor, but no one except me notices it. Very odd as you cannot tell by looking or touching the shoes. The soles must be made of some special rubber. I would definitely be carefull using them for step or high impact. For dance and low impact sliding all over the place can be fun.