Still don't know why it used the UK store, but I have fixed the problem.
I selected every item by clicking one and then using command-a. I then mass changed the country from uk to us. I then deleted the contents of the retail value, current value, and features (some British spellings). This step probably wasn't necessary. Refreshing the data from Amazon did not work. However if you hold down the option key the menu item changes to REVERT to Amazon data. This erases any custom images you put in but fixed my problems by using the US store data.