As I said, there are a lot of purchased accounts in the Philippine section. It's only a matter of time so that sooner or later they show themselves.
Buying accounts aren't prohibited but we must make sure that they will never abuse this,
if these accounts were to be found on the same Campaign then tagged them.
Not only if they are found to participate in the same campaign, but also if they apply to the same campaign or contest with multiple accounts. The intention of cheating is sometimes easier to detect than the cheating itself.
If sufficient evidence is provided, those participants should be tagged to warn the community before the act takes place.