It's not the compensation that is the issue.

It's that lot of people managed to get sasuke/sakura and on top of that managed to get ninjas from food bag while it was priced at 10cp... HOW do you want to compensate those who didn't do that? You can't because it can not be compared.

And that leaves you only with two options:

1.) Take everything that was earned from those faulty events back and issue return

2.) let the players keep it but then allow rest of the player base to do the same

So my question is. Are you going to do roll-back or are you going to leave players getting unfair advantage that will be "compensated"?