The tobacco company will still thrive. How many people do you know that buy blunt papers? How many spark up a menthol after they smoke bud? And when they can't smoke bud at work, how many go on a cigarette break?
Plus, the gov't would make money off of it if they treated it like alcohol. I know other laws are a lot more lenient than PA, but here you can only buy beer in a licensed beer store. You can only buy liquor in a liquor store. And you can't make moonshine.
If that were weed, you couldn't buy it anywhere but a gov't regulated store or somewhere with a license, plus you couldn't grow your own without a permit (maybe for medical users).
As for dealers who want to still make money, instead of legalizing, we could decriminalize. The government won't regulate it and won't make any money off of it, but if you get arrested, there are no penalties.
Fuck the system.