I was a player on Party Poker which was the original site for many years. About 7 years ago the government told all the sites to quit letting US players play for real money. PP complied and sent me my funds back. Full Tilt, Absolute and a few others chose not to comply and the Feds shut them down and froze all the money. I played some on Full Tilt but not for real money.
The ready go's and MPC on WGT are no different than gambling. The feds won't hit up the WGT until it beomes much bigger. Keep in mind these poker sites were running the deposits though off shore accounts and overseas account to avoid the US regulations. They got what they deserved under the current laws.