Yes, but medical marijuana is a lot less important to pharmaceutical companies than recreational marijuana is to tobacco companies. Pharmaceutical companies care less about medical marijuana these days than you might think.

And it's not so simple, because it's not so easy to see how money gets directed. For example, Altria is a massive, diversified company (albeit less so since Kraft Foods was split off). They likely see their investment in smokeless tobacco ("e-cigarettes") as a lateral move to help them corner the marijuana market once it's legalized. They also see it as a hedge against the decades-long drop in tobacco usage. But which is it? The answer is "both" - weighing those against each other is tough. And it gets even more tough when you try to consider how much they would have considered the loss of the tobacco business to be a threat back in 2006, when their business also included production of cookies and macaroni & cheese.

These incentives are oftentimes conflicting even within the same company, so from the outside, we can't just say "well, industry $X is larger than industry $Y, so they will get their way". They have to decide that the issue at hand is actually more important to them, which isn't so obvious, and that's even before you get into the fact that those industries may actually overlap.