The sonic shower is "futuristic". That's why it's there, which is fine with me. I also think a small amount of water would probably be necessary after whatever it shakes off of you falls to the bottom. Running water of some kind is a necessity in the quarters, beyond what you get when you order a beverage out of the replicator. I also think a sonic toilet would be even more implausible than a shower. Maybe a sonic bidet. Doesn't sound appealing.
And how exactly is laundry processed?