Oh, it is...
McDonalds have gotten away with this statement for years now because it's not a descriptor of the product contents, it's the name of the company they buy their burgers from.
Incidentally, it's also a wholly-owned subsidiary of McDonalds.
(
Kerrisis There's someone in my head, but it's not me.,
Mon 25 Feb 2013, 23:55,
archived)