Because the defined car free movement doesn't love cycling more than it hates cars. It is political and does have an agenda. It is primarily aimed at urban dwellers with a dismissive attitude towards metropolitan and suburban dwellers. Whenever there is that kind of division there are two sides no matter what. The message is do it our way or there is a class struggle, social struggle or environmental struggle and only one side can be on the right side. Why else would sprawl be used as a bad thing? Notice the link dealt with that issue as well.