Funny thread! I honestly don't think I've ever been out tarot shopping whilst under the influence. Now there's an idea...
I suppose I have taken a gamble on decks and found that they really weren't for me. I haven't so much bought on a whim either although I have been through phases where the inner completionist has got the better of me and I have bought a deck because I really OUGHT to have it and then it's been completely unused - like the Tarot of the Old Path or some thematic LoS decks when I really was trying to keep up with
everything LoS published and ended up with decks like the Black Cat Tarot and Elemental tarot - just useless to me - and LoS decks like these don't budge in trading either so there's no point even going there.
I have - on reflection - bid on ebay stuff whilst tipsy after dinner parties - but nothing that I can remember regretting. Except perhaps one. An old majors only RWS that looked really mysterious and had belonged to someone's grandfather and the seller could say nothing about it and foolishly I didn't ask for pictures of the backs - but it just sounded way too tempting so I bid higher than I should have and when it came it was pictures of the RWS from a magazine glued onto cereal packet cardboard. The backs really were just cardboard from a cereal or biscuit box or something