That's probably because Americans call sweets 'candy', and King would have had to have employed van drivers all over the country to drive around and enforce King's trademark.
Yes, I know that was a deliberate misunderstanding for comic effect.
Anyway. In a statement sent to Kotaku, a King spokesperson explained the real (and much more boring) reason behind the abandonment of the claim.
Reasons and stuff
"King has withdrawn its trademark application for Candy in the U.S., which we applied for in February 2013 before we acquired the early rights to Candy Crusher.
"Each market that King operates in is different with regard to IP. We feel that having the rights to Candy Crusher is the best option for protecting Candy Crush in the U.S. market.
"This does not affect our E.U. trademark for Candy and we continue to take all appropriate steps to protect our IP."
So, that was about as exciting as you'd expect. All of this has no bearing whatsoever on King's trademarking of the word 'saga', which is the basis of a legal kerfuffle between the casual puzzling behemoth and the maker of The Banner Saga.
We'll keep you posted if King tries to trademark any other common words. Maybe it'll have a crack at 'king' next? Or 'pear'?