Before you become a parent, you often needlessly load yourself and your household up with crap, thereby necessitating playrooms and hardly anyone has room for that. According to Fireflies in the Clouds some of the worst offenders in terms of useless baby supplies include baby pacifiers with fake teeth, massively fancy and expensive cribs, and unusually complicated baby washing tubs and related products. In an earlier Stroller Derby post, Jay added wipe warmers and microwave steam sterilizers for bottles.
Personally, I also don't think little Billy needs Leap Frog, Dora, Graco Pack N' Play, or Waldorf wooden train sets. Kids don't need anything but a rock, two boxes, and some sticks to have a great time. And you, the parent, need little other than a nice bottle of Chardonnay, some fresh air, and the occasional date night to get through that first year. Oh, and possibly some faulty condoms (to make a nice wee sibling, the only toy that never breaks).