I can see the government's position on this. I'm a federal employee, and a veteran, although not a disabled vet. Disability pay is to compensate those who can't work and have no other income. A civil service employee can't retire with a civil service pension and still receive either workers' comp payments or a disability pension (federal or military).
However, I don't mean to demean the sacrifice of America's disabled veterans. Maybe there's a compromise possible, such as a lump sum payment to compensate them for pain and suffering.
I've got a compromise solution. We throw away $15 billion a year in foreign aid. Let's redirect that to disabled veterans. Incidentally, I'm a combat veteran without any disability.