I hope this is not against the ToC...frankly, I can't see how it could be

My server population is rumored to be 2.25:1 in favor of horde. I took a look at the prices of high end mats and they're significantly cheaper on the horde side. I had created a bunch of rogues for the pilgrim achievement and ended up parking one in Org and using my ally druids, I escorted another to Booty Bay. I put up some junk for sale on the horde toon and bought it using the ally toon. Wow, needless to say I was a bit shocked by the AH fee charged for this. I offered up the junk at around 1k gold. I think the AH fee was like 150g if I'm not mistaken.

Does anyone else here do this?

If so, is the rate charged by the neutral AH a scaling one? or is it always a fixed %?

Is there a more effective way?

Thanks for your help as always.