Rusty doesn't want to have anything with Tommy's addiction.
But, I doubt Tommy knows about Rusty's drug business. Rusty probably didn't tell him cause he's junkie, he can't trust him. He's using Quinn to sell his stuff - I don't know where he gets that but we know Quinn is dealing with everything, including steroids for jocks and Quinn/Riona conversation showed that Riona wants out of that drug business.
Thing is:
- in 0.1, we learned from Maya DIKs just showed up one day (4 years ago precisely), bought a big mansion and nobody knows where they get money from;
- in 0.2 we learned Tommy is junkie from Josie; later we learned same thing from Heather/Quinn when Heather said how he is stealing from her stash - that confirmed he's just a junkie;
- Rusyt is rich - he paid for the whole club in 0.3 and he gives max. $ to MC if he'll spend all in the club. If he is a rich kid, he would be with Tybalt but he isn't there. Why? Unless his money is not from something legal and he doesn't want others to know that;
- IMPORTANT: now, the whole story is based and progressing because of the CUM-petition. Without that, Mc and Derek wouldn't do anything in this game. Story-breaking plothole is: HOTs came and helped with CUM-petition because "Tommy made an offer they couldn't refuse". What could piss-poor junkie offer to Quinn? Unless he was sent by Rusty - who has money. Without that offer, there wouldn't be CUM-petition and there wouldn't be rest of the game.
Now, it's possible Rusty have money from something else but we didn't see any other clue so far.