Could it be that the Rosetta Stone V. Google lawsuit rising from the dead is playing a part in this? A number of companies (including Ford) are supporting Rosetta Stone in their suit against Google for accepting keywords that include trademarks. An appeals court just resurrected this suit thought dead in 2010.
Revived Rosetta Stone Lawsuit Spells Trouble for Google
No, this has been the standard for a long time - there wasn't any change. Realistically, I don't think that suit will move much farther forward.
The reason Google does this is just a balance of risk vs. reward. There isn't a system in place where they can effectively manage trademarks, so the potential for suits is larger than the potential for increased spend.
When Google finds a way to effectively manage trademarks, they'll ignore the manufacturers and move ahead. It's just a risk / reward calculation for them.