I don't like ketchup.

I enjoy ketchup on select things (usually on unhealthy things) ~ like fries, hamburgers, mac and cheese, etc. I get a kick out of how in certain countries, namely the middle east and certain parts of europe, "spicy ketchup" is actually as popular as normal ketchup.

This.
I didn't think there would be much difference in them.

I don't like ketchup on anything, I prefer mustard but I love tomatoes.