Limit the RV spaces to people from Seattle and you have my support. If it turns into the parking spot for all of the Puget Sound's homeless RV-ers then no.
How about a new rule that says if you park your car on the street (like a freeloadin' TAKER expecting the city to subsidize your motorist-lifestyle) you have to leave it unlocked for homeless people to sleep in.
I'm not sure how you limit it to people "from" Seattle.