Reverse the situation though, and I'll use a current transaction of my own as an example:
Several days ago I put in a take on a four figure book, and payment isn't expected till the thread closes sometime next week. Say next week rolls around, and instead of paying I tell the seller "Oh sorry, I spent all my free cash flow in the stock market last week during the downturn. I can't buy your book anymore."
The seller naturally gets upset with me, and I come back with "well its my money, and I've been in the hobby for x amount of time, and I've done transactions with persons x, y, and z, and my rep is great. And after all, its only money."
Do I get a reprieve from the PL because I've been around the boards for about 5 years and have paid for 100% of my previous takes? No, in fact I should know better than to renege on a deal like that, and my dumb*** should be on the PL until I've made things right by the seller I wronged.