However, all you'll do is reduce the average employee skill to can-just-about-do-FizzBuzz levels. That is not good at all. And since you can raise the 'average skill of the programmer' by just allowing jeans & tshirt (which costs nothing), it seems like a sensible investment to make.
A lot of huge corps won't care. As long as they can muddle along (with the help of consultants of course). The phrase that I see a lot of for this is "not our core business".