The majority of strains are a hybrid of some sort. So in reality it is EXTREMELY rare that anyone is ever getting 100% indica or 100% sativa strains (even rarer for sativa). Most people don't know the difference, or have ever even heard of either though.

Its hard to ever be sure of whether or not bud is indica or sativa, so you cant blame your dealer for not knowing.. thats absolutely ridiculous. Most dealers see a lot of different bud so they cant be keeping track or anything..