When I decided that couch surfing just wasn't doing us any good, and got rid of the last one - I immediately had two different people "in need" that only wanted to use the couch for a few weeks.
timenchanter and I manage to reduce the place to just the two of us, where there's some breathing space for packing and cleaning up, and within a week someone needs emergency housing.
A previous tenant, having been kicked out, came back with a boyfriend the next day asking if "they could use the shower."
Now I have Mena trying to come over and either give Mellie baths, or do loads of laundry.
And each time I say "no," I feel like a grade-A jerk. Of course, then I remember what the house looked like before the grand procession of users came through...