I deem this poll insufficient, there is a clear bias towards American only fast food restaurants (Of the ones listed, only Burger King and McDonalds exist outside of America) This will screw the result in McDonalds/Burger Kings favor since none Americans can only vote between those two.
There are two ways you can fix this problem, either remove all fast food places that exist in only one country, or add restaurants that exist it other countries. For example, in Sweden we have: McDonalds, Burger King, Sibylla, Max and Frasses.