I think that it is pretty funny that they think that is a serious bug. What do they want you to do, go back a rewrite the basic rules of logic.

Tell the customer that even thought they think they want sales in Texas and California, what they actually want sales that were in Texas and sales that were in California which is the same as sales in Texas or California. They probably will not understand this however.

I know it is probably not funny to you because you have to deal with these people, but thanks for the laugh.

Ryan