These are my voluntary, private giveaways
Technically, you violated a contract with the participants, you pledged to give prizes to the winners, and thus, people participated for that reason, any participant on one of the 4 contests you canceled can technically issue a flag type 3 against you for violating a contract, myself being one of them won't do it because you nicely invited me back then when we were "good friends" long before you read my comments in P&S -- although now that I think about it, I think I was never your friend, I was just another "well established" member that you used to increase your power on forum, your lobbying skills are indeed top-notch to say the least.
Unfortunately I have to agree with this. Same thing goes for the Ratimov deal, I feel you guys are in the wrong and should pay out the prizes promised. In your case it's under 100$ in his case much more, but the amount doesn't matter. You made a commitment IMO and should honor it.