TomTom uses Linux, but doesn't support Linux users

Having bought several TomTom One navigation systems here at work (Italy), I was browsing their web site to find information about maps. There are several pages of documentation about their devices. In one of them, they proudly inform you that their devices use Linux, as a warranty of power and stability. But, when you come to the software (the one used to manage updates, set locations, etc), they only support Windows and Mac OS. Not that surprise, and not that the software is really necessary. But the point is: they probably saved million dollars using a free kernel, and they didn't even care supporting Linux users. Am I the only one disappointed?