United Healthcare pays 50% of the standard commission on GI business. At least they do in my state.
Some carriers will term your contract if you write too much GI biz. That's another reason not to burn your bridges, especially if it is a carrier you use on a regular basis.
Maybe carriers like UHC don't care and are like Mikey (Life cereal) . . . they will take anyone who fogs a mirror. Those chickens will come home to roost eventually . . . even for a big carrier like UHC.