I had a child Sim go to the kids camp for two days and I noticed that her bladder and hygiene needs decayed extremely slowly. So slow that it feels like cheating.
The other participants seem to be affected as well: during a two day long Getaway I saw NONE of the other Sims use a toilet or shower a single time.
I tested this only on the kids getaway (default lot, default schedule), so I'm not sure if all kinds of Getaways behave the same.
