>>77654847I've honestly wondered this before. I believe it is likely a result of the same thing which caused "What do you do?" to become an acceptable way to ask what someone's job is; the full, "correct" phrase would be something along the lines of "I have (a duty / an obligation / a desire / an inclination) to (action goes here)." Since everything in the parentheses is variable but easily intuited via context and the structure is quite consistent, it's easy to imagine people dropping off sections when speaking hurriedly or drunkenly. This is the only explanation I can come up with, given that "have" is used to show ownership at all other times. Declaring that you have a motive for what you are doing makes sense, y'know?
"I must (action)." is another one, but much cleaner, so nobody is bothered by it when you simply declare "I MUST!" each time you're asked why you rape.
