[reeses]

If the US government were to take action on this, the mostly likely consequence is seizure of the funds. They'd target the site itself, which might give them a list of names (which, at the most, they'd lateral to the IRS for fun).

Otherwise, the site would disqualify the campaign and return any funds.

[dnautics]

(edit to above): I think the likelihood of severe negative consequences is low, but there is a nonzero likelihood of being targeted for a bad experience, for varying values of "bad experiences".