I don't own a stallion, but if I did, I would certainly decline people if the circumstances called for it.
If I had a LWO positive stallion, I would decline LWO positive mares. Any responsible breeder would. Same with any other genetic diseases. Poor conformation. Poor health, including feet not up to date, poor weight, wormy belly etc. Not up to date on shots/coggins that are required for breeding mares. And if I was rubbed the wrong way by the owner, I would decline them.
As a stallion owner, you should only be interested in producing the best quality foals. You shouldn't be looking at dollar signs. Sure, 10 people might want to breed to your stallion at $1000 per mare. Only 4 mares are what you would consider breeding quality. Are you going to turn down $6000?
You must be a responsible stallion owner. (Not saying that you aren't, but I'm just making a general comment)