To regulate simply means to make regular. The commerce clause has been interpreted quite broadly along those lines.
- First, Congress may regulate the use of the channels of interstate commerce.
- Second, Congress is empowered to regulate and protect the instrumentalities of interstate commerce, or persons or things in Interstate Commerce, even though the threat may come only from intrastate activities;
- Finally, Congress’s commerce authority includes the power to regulate those activities having a substantial relation to interstate commerce (i.e., those activities that substantially affect interstate commerce).
http://en.wikipedia.org/wiki/Commerce_Clause
Whether or not it facilitates commerce seems to be irrelevant. They simply have the power to regulate. The main question is whether or not they can use it to force people to buy a particular product or not. But they probably can.