Brilliant, a bunch of "hackers" who a lot of the world looks down on - is going to try and educate people about cannabis.
This pisses me off and i'm a toker, all your average persons gonna see is a bunch of lame criminals promoting drugs. Thanks, but i'd rather have someone reputable fighting this cause. Fuck you anonymous!
Anonymous are not a bunch of "hackers", there are some groups of Anonymous members like Lulzsec/Anti-sec and Cabin Cr3w that are comprised of hackers, but the majority of Anonymous "members" are every day people like you or me, usually activists with some interest in seeing change in the world.
Anonymous is regularly discredited because the whole idea of Anonymous is that anyone who wants to claim to be Anonymous, is Anonymous, this is no organisation with membership, if you say you're Anonymous, you are Anonymous. All it takes is for Mr Hacker to say "This was on behalf of Anonymous", and that's all that will be reported by the media.
Please don't blindly believe everything the media would like to have you believe. To call Anonymous "hackers" is like calling Muslims "terrorists", some Anonymous members are hackers, just as some Muslims may be terrorists. The vast majority are not.
Regarding the Op, I think it's a good idea. I don't think they'll lose any support Folley, most of the larger more well known groups that use the Anonymous name like YourAnonNews, AnonyOps etc have been behind supporting the legalization of Cannabis for quite some time, it doesn't seem to have affected their support.