Interestingly, Fry Sauce[0] is near ubiquitous in Utah (and no other US state as far as I know). You can find it on offer just about anywhere in Utah that sells fries.
0. https://www.eater.com/2016/8/6/12054512/fry-sauce-ketchup-ma...
0. https://www.eater.com/2016/8/6/12054512/fry-sauce-ketchup-ma...