Ironically, prices would probably be lower, and we'd have more part options, if we had fewer vendors. There just aren't enough Vipers out there to support a big ecosystem. Every time a new vendor comes onto the scene, it makes it harder for the established and trusted vendors to benefit from the economies of scale - and pass those on to us. Also, as Steve noted, there is a big disincentive to innovate if you put all the up-front R&D into new product just to have a competitor copy it and sell it for less (since they don't need to recoup the development expense).
If we really want to advance the state of the aftermarket Viper parts situation, we should focus on helping the trusted and established vendors succeed. I don't know a lot of those guys personally (like shooting the $hit in person and throwing back a bunch of beers) but from what I know through this site, I trust that they'd do right by the Viper community's efforts to make them more successful. Oh, and if any vendor rubs you the wrong way on a certain day, keep in mind that we're all just human and try to imagine the amount of personal presure these guys are under - making payroll, maintaining an inventory, dealing with being undercut by competitors who haven't really invested much, difficult or impossible credit market, looking at an economy that is shaky at best, etc. Let the personality quirks slide, don't take things personally, and focus on the end results.