Sure, but then that opens up a lot of questions about "is this actually a free market?" It certainly makes sense in a space that is one - if you don't want to

Sure, but then that opens up a lot of questions about "is this actually a free market?" It certainly makes sense in a space that is one - if you don't want to be tracked by e.g. an online newspaper, there are certainly plenty of alternative offerings on the market. But what if Comcast wanted to track you? Depending on where you live you may not have the choice not to do business with them, which means your desire not to be tracked gets steamrolled by your only available option - you're forced to accept tracking or be denied access to the internet.