This idea has been proposed a number of times and is most often seen in relation to vehicles. At issue is the need to go to a dealer to get some things fixed. Independent service providers don't have access to the computer diagnosis or update software and thus can not fix everything. I have seen this from both sides (I have provided service as a dealer as well as independently). Manufacturers charge service companies money for access to proprietary information. This guarantees some level of work for that provider at least for that manufacturer's product. If all were allowed access, then there would be little to differentiate service providers. Also, who would provide warranty service? Given what little is paid for service under warranty, at least having access to the service information will hopefully create more non-warranty work.

Dan