I think has more to do with how varied it is how you want your ketchup on your burger. Ie. some like to put it on the patty evenly while others dip. FWIW, this

I think has more to do with how varied it is how you want your ketchup on your burger. Ie. some like to put it on the patty evenly while others dip. FWIW, this is also how ketchup is served at backyard bbqs: you give your friends a "dry" burger and direct them to where the ketchup, mustard, and other condiments are.