We were on a family trip home after many years living overseas, a long haul flight we splurged on business class seats. When trying to book flights there were not enough business class seats but were advised to pay for business class seats to ensure priority waitlisting, this we did with no advice on what would happen if the seats did not appear.
Well the seats did not appear and somewhere in the fine print (never found) it says we were not entitled to a refund.
Not even a complementary free upgrade!