The rule doesn't make any sense to me either, you would think they would give you more, to use them instead of another agent or web site.

But, sadly, its a rule and its posted, so it is what it is.

When working with travel agents lately, I have often been able to work it out where they book part and I book part, and they have all been willing to go along with it, so I get the best of both worlds. Agent discounts on activities, and hotels that don't have rewards programs, and I book the other hotels and air myself and earn maximum benefits. I had an agent get me $50 off a night at a MO over what they would charge me, with a free room upgrade, and she still make a commission.

Try that with another agency and see if they can get you a good deal.