Tried it too after swearing off ketchup for years. That sweet and tangy taste actually works perfect with the meat, makes it way better than you'd think.
What is it about ketchup that makes everyone hate on it so much, then secretly love it on things like meatloaf or burgers? I used to be a straight mustard guy, but then I tried mixing a little ketchup with some Worcestershire sauce and it was game over. Honestly, that sweet and tangy combo is just hard to beat when you're grilling.