Playing house concerts sure, that's been around since people have been living in houses I'm sure. Asking strangers to book you and also get said strangers' friends and family to come pay a band they've never even heard of and may not even like? Nah. That's just a poor attempt at filling an off-night on their tour.
That's what I thought at first, but with the cool stories here it sounds like a cool thing to do. I guess if you are wanting to book these in an area where you don't have a network, CL is one way to do it.