I had an old roommate do this. He purchased plane tickets from American Airlines and they had the option to pay through PayPal. He choose that option. Money went through, and tickets were immediately canceled by A A. He called them and they said "that's a bug that happens sometimes. The tickets will be refunded in 5-7 business days, just place the order again and it should work."
It didn't work.
He called them again at 805 the next morning. He got told the same line. He refused to hang up until it was made right. He was on the phone with that poor agent for 11. 5 hours. Eventually she just said" look sir, you were my first call of the day and I'm now on overtime, I'm transferring you to my manager".
Manager did make it right, he got free tickets(about $800 dollars), an additional $1600 on future flight vouchers, and about a week later the transactions were reversed. He came out of it with 2400 in profit. That said 11.5 hours on the phone making small talk with customer serviceand refusing to hang up might just push me over the edge.