i've always just thrown mine in the washer too. and dryer. Never had any problems. I usually try to "squeak" them when taking them out of the washer to get the water out. but most of the time when I wash toys it ends up being on an "accident" because they will hide the toys in the piles of dirty clothes when I am doing laundry.
Or if I feel like a toy needs washing I will put it in a pile, but they aren't really messy with their toys so they don't NEED to be washed too often.