In the UK the burger and fries market is fairly squarely cornered by McDonalds, KFC, and Burger King. McDonalds is unexciting but cheap, KFC is generally better as long as you like chicken and avoid the on-the-bone offerings, and Burger King is generally the best all round at the cost of being the most expensive. Inevitably McDonalds is by far the most numerous and is therefore the one I end up eating most; separate McDonalds were the closest fast food joint to both my university halls, and it's the only one in the nearest town to me. (The nearest city has all three, but it also has rather nicer offerings outside that group.)