Tired of sitting next to caterwauling babies and tantrum throwing toddlers on airplanes? Wish Crate & Barrel would have a "I'm doing my part for population control" shower registry option? Feel alienated by friends/family who have recently spawned? We PROMISE no one in this group will ever ask you "Do you have kids?" and you'll never be trapped in a corner by a parent boring you with cutesy photos and potty-training tips. Whether you're hitched but never hatched or single and don't believe in …