THE ONLY reason I can think of right now is because the seller hasn't sold anything around $1800 (or whatever you paid for your pedals). It doesn't matter whether or not they're a Powerseller.

i.e. Seller is solely a cellphone case store and usually sells items for $5> . EBAY sees they sold something for $500 out of nowhere - it raises suspicion that the account might have been hacked. Most hacked accounts have these ultimate/awesome deals that do not reflect their selling history. I remember last summer a hacked account was trying to sell a high end bike for half the usual retail price. I tried to toy with the hacker and I knew from his payment instructions that he hacked the account.

I've been buying/selling on EBAY since 2003 and I've seen almost everything on EBAY.