it's a case of the old dealership system being so involved and expensive right now, that gm/chrysler/toyota/whomever just can't stop it... the job losses, the lawsuits, and all the rest that would come with manufacturers switching to "factory" stores is just too big a hit to take...
so rather than take that big hit, gm et al just want to prevent tesla from being able to start their marketing properly and in a smarter fashion...
not really fair. why should tesla be penalized for someone else's poor business plan and lack of long term strategy. being able to find ways to make a product less expensive for the final buying public should be rewarded, not penalized.