That is exactly my thought and funny you should bring it up. We are tracking phone calls made by customers to a business and where the call was made from.

The consulting company we are working with wants to put the phone number and lat/long in the fact but my argument is it belongs in the dimension as it's not a measure. Should the number be called more than once, storage is less on the dimension than on the fact. Chances are though , either phone or lat/long will most likely appear only once in the data but it's still not a fact and belongs in a dimension.