Corporate Travel Officer: "Hey we are going to sign a contract with an airline for all our airline needs for the next 12 months"
UA Corporate Sales: "Cool, how much do you have to spend"?
Corporate Travel Officer: "Probably $50M or so split down the middle domestic and international, we're a big company. What can you do for me"?
UA Corporate Sales: "I can get you 5% off all domestic and 3% off all international annually. That's $1,25000 and $750,00 savings respectively".
Corporate Travel Officer: "Sounds great. Anything else that you can do for us"?
UA Corporate Sales: "As your company is based at one of our hubs, I can throw in some other stuff here and there. How about your Exec's get our top tier status, Club access,etc"?

Contract signed and money committed.

Playing that out, what does UA have to lose by culling a bunch of GS from corporate contracts? If the people that are doing the flying don't have a say in the contract, why would UA care? Trying to think like Kirby on this one and come up with an explanation of why it seems the corp contract GS are the ones getting cut.