A couple things are worth pointing out here. First, many women are very social-validation oriented. They date with the agenda of impressing other people in their life with the guy they catch. Such women are not thinking independently about whether they can respect a guy who lives car-free or not. They are only concerned whether other people will be impressed with the guy or not. So unless you're into, and can find, an independent-minded woman, there is a high risk that you will have to impress not only her with your lifestyle but also everyone else she's interested in impressing, which can be a tough, if not impossible burden. If you really value independence, you might want to consider staying out of relationships altogether, or at least stick to dating women who are more concerned about gaining your respect than having you work to get hers.

Second, I can't stereotype because there are many women who are flexible in terms of aesthetic orientation but having said that, a woman once spoke at a public transit meeting to make the point that sitting at a bus stop in panty hose and big hair is too hot. Many women also steer clear of bike commuting for this reason. I'm not saying that many guys aren't the exact same way or that there are no women who are willing to sacrifice personal aesthetics and some comfort to go car-free, but feminine aesthetics are slightly stricter in most cases than for men so it could be slightly harder for a man to find a woman who accepts and even appreciates his car-free lifestyle as it would be for a woman to find a man who accepts and appreciates hers. Now that I say this, I will probably get replies about all the men who expect a woman to don a perfect appearance, etc. There are exceptions to all rules.

Also, now that I think about it, there are plenty of women who can be really charmed by a guy who puts extra effort into life by living car-free. Many also appreciate principle and the willingness to make sacrifices for it. It demonstrates a good heart, good ethics, and responsibility generally. You just have to steer clear of those women who twist your lifestyle into some kind of shirking of driving as a responsibility. Probably being with this type of woman wouldn't make you happy anyway in the long run if you are the type of person who has the ability to shirk social norms for a higher cause.

Also, women like a guy to be in good shape if they aren't the kind of women who want guys to be worse than them to make them look good in comparison. A woman who works to keep herself in good shape will appreciate the physique you have and will maintain longer in life because of your commitment to walking/biking. Staying fit is not as easy as letting yourself go, however, so there are less people in both gender categories who do so, which narrows your pool of potential good candidates for a mate. It can be lonely at the top.