And how would they program that keyboard? Why should they need to buy extra hardware? Instead, it's offered on every copy of Windows, and activated in a standard way that doesn't require multiple simultaneous keys. They can walk up to a library shared computer, or something at work, and start using it.

It's annoying when it gets in the way of gaming, but face it: pressing shift 5 times is not something you do accidentally in most apps outside of gaming.