I have my son's Study Abroad UK address as one of the options on my Manage Your Kindle page and I frequently find a UK price that is much cheaper than the US Agency pricing. Especially for UK authors such as Marian Keyes etc.
I admit to having my Kindle home hopping back and forth to get better pricing and/or availability way too often but I sure do hope Amazon never stops me.
Sadly I expect the Publishers will eventually try to have me arrested.