Ebay sellers like Get It Digital are known to have some of the lowest prices for Nikon and Canon gray market cameras and lenses. It seems that Canon USA is not happy with that and have filed lawsuits against several retailers to stop selling gray market gear in the US. Photographybay has a detailed report on those lawsuits:
"Canon USA filed a pair of lawsuits in October against Get It Digital, LLC and several other widely-known gray market retailers in a effort to force them to stop selling gray market Canon cameras and other products in the United States.
I obtained copies of the complaints and exhibits late last week and have reviewed the allegations made and evidence cited within.
In short, Canon USA cites US trademark statutes to argue that, because it is the exclusive licensee for the US market, the federal court should order the defendants to no longer offer imported Canon products for sale."