Hmm yes there are multiple reasons. If you were to survive a nuclear explosion you are probably going to go through a slow and painful death that can go from minutes to years.

Depending on how affected you are, you can become literally poisonous to touch. And that's just for people affected by the explosion. Then there are the people that won't be able to go back home because of radiation. That's a different kind of pain. And yes, bombs also can bulldoze cities, but at least you can recover and reconstruct