Can I use ketchup to hide smelly fingers?
Why would you use ketchup to hide smelly fingers instead of cleaning your hands?
I didn't know that was a good choice but it was the only thing I had
You should wash your hands correctly. Having ketchup will just make your hands more dirty.
It's not that big of a deal
You're right, it's not a big deal, since cleaning your hands is so easy. You will feel more comfortable and cleaner if you wash your hands instead of making them dirtier with ketchup.