This sounds quite like 'Market Basket Anaysis' -- e.g. of the people who bought Coca Cola, what products did they buy?
This type of analysis requires a "self join", where you can use a filter on one copy of the dimension (in your case, Location) but still display the other copy in full. Take a look at the following knowledge base article for more info and see the attached file for a working example
Self join example.twbx.zip 1.6 MB