Mariannalee,
Perhaps this link will answer some of your questions.

http://www.latestcasinobonuses.com/is-gambling-online-illegal.html

It basically comes down to the new law stating it is illegal in US to transfer moneys direct from financial institutions to online gambling venues. This also goes for reverse, ie gambling institutions to financial ones. This is why an e-wallet account of some sort as an intermediary is used.