I would have said Plants vs Zombies 2
I very much enjoyed it initially. I even bought some in-game stuff to thank them - stuff that would improve the game, not magic beans you buy as they've crippled the game otherwise and will be buying eternally.
I thought it was a very pleasant and pragmatic of the 'free to play' model.
Then one day I got a massive game update, whole game changed and I'd been nuked back to the beginning and chucked some magic beans.
I can only assume EA had noticed PopCap had snuck out a decent game and were mortified.