A while ago, Bleep! member Ariella B. told me about a study she heard about. People were told to place their hands into buckets of freezing water. The first time, they weren't allowed to say anything, and had to be completely silent. The second time, they were allowed to say anything they wanted to, including curse words. Participants agreed that the water hurt their hands much less the second time around, when they were allowed to scream out whatever they wanted to, and curse.
This makes total sense. It's the reason it's a natural reaction to say "ow!" when we stub our toes against a wall, why we flinch when something gets too close to our faces. However, you can say "ow!" and yell and scream and express your pain, but you don't have to use curse words. It's just unnecessary. The English language is so rich, and has so many words for different occasions. Why not use an alternative to a bad word?