Re: can you buy GW2 for mac?
No, unfortunately it is not currently available for Mac.
If you wanted to play it on a Mac you would need to have a copy of Windows and run it through Bootcamp. Before going through that hassle though, you should check the requirements to see if your machine will run the game: http://www.pvzgw2.com/news/plants-vs-zombies-garden-warfare-2-pc-specs.
Hope this helps.