It's because there are only a few DMS (dealer management system) providers that most dealers sign up and stick with. They manage not only their web site, but a lot of back-end systems as well. These systems, like you pointed out, don't do a very good job with the web site, but that's only a small part of what they offer as a package.

Since most dealers aren't very technical, they just stick with what they get and leave it to the so-called "professionals" to handle the web site.

There's always room for disruption, but it's going to be more difficult than simply calling up dealers and telling them you can create a better web site.

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