Ugh, here's one. When sellers obviously profit off shipping. I bought a box of chocolates off a deal site, and only after buying I realized that it was for store pick-up. I e-mailed the store owner and asked if I could possibly have them shipped; if not, I could rearrange a pickup. She said no problem, they ship all the time, and shipping would be $10--which was nearly half the purchase price (it was $30 worth of chocolate for $15.) I assumed for that price she'd be shipping in some temperature-controlled type box with a cold pack or something, as it was early summer.
Nope. The box showed up with a sticker showing she had paid $2.80 to ship my box in a regular box. $10 shipping for 8 pieces of chocolate. She basically made up most of the price "lost" by the online deal. Her chocolates were beautiful, but the gross overcharge left a really, really bad, un-chocolatelike taste in my mouth.