Because his fiancee is a cantaloupe!
Cant-elope
So that the bride wouldn't get cold feet.
Because they cantaloupe. (The wife thought of this one... hopefully nobody else has posted it)
Cantaloupe...
Because they are planted in the spring!
One is fun to smash with a sledgehammer and the other one is a watermelon
Because they can't elope!
Fiancee.
Even though my existence is meaningless I want to spend the rest of it with you.