Although you may be disappointed, it is up to you to read the description. If you really like them, get some more! I did something similar with Steam-a-Seam. I thought I was bidding on the one with paper on both sides, what a shock when I opened that package. I also wrote to the seller, who pointed out a small blurb referring to only paper on one side. So it was my fault. No big deal except I had to go on a quest to find what I wanted.
Lately I've been looking into charm packs. Now those vary greatly! I found anywhere from 21-64 in a pack at various prices which don't necessarily correspond to the quantity of squares in the pack. I saw larger packs cheaper than smaller packs. Maybe it goes by what's popular.
Now I look for the fine print to be sure I know what I'm getting for the price. :) Don't be afraid to ask the seller questions. The only problem is if the auction is almost over, sometimes you don't get an answer in time. But many of those sellers have the same items back out there again.