A question for Travis Lewin or other legal-eagles out there ...

The Bellagio robbery suspect is being charged with 2 FEDERAL counts --
One for a prior bank robbery (which I understand, as that's been Federal jurisdiction for years), and also for
"interference with commerce by robbery" in the Bellagio robbery. See story link:

http://www.lasvegassun.com/news/2014/jul/30/federal-charges-filed-against-bellagio-robbery-sus/

Is there something special about a casino robbery to make it federal (vs. Nevada) jurisdiction? Even though gambling is state regulated?
Was it the amount of money involved? Or just that the perpetrator was an a**h**** ?

Normally robberies are state-level crimes, like robbing a 7-11 store, so I didn't understand the "interference with commerce by robbery" federal charge.

Just curious, not contemplating such a caper!