You are not the first, and won't be the last to have something like this done to them by Illtech. They've never done anything to me personally that was wrong, but I know of a lot of the shadiness that has gone down there. Simply search them on the Subaru forums and you'll see. I'm not the type to bash on anyone or a shop, but they just keep doing it to people.
I'd call my credit card and dispute it. You can at least stop the charge.
Modify your car for a function and purpose, not just to follow the crowd.