I'm willing to work hard for my food. I'm willing to devote time and energy to preparing a meal. I'm willing to work hard to earn each bite (as one must with, say, a grapefruit). But once a bite of food goes into my mouth, I should be done working for it. Once it is in my mouth, that is the time to just take pleasure.
So I avoid watermelon, because I don't like having to work out the seeds while the watermelon is in my mouth.