I'm guessing it has to do with the belief, in some circles, that it's healthier to the baby to delay washing off the vernix (it holds moisture and has antibacterial properties). Even those who advocate for it say it's mostly absorbed in the first 24 hours so after that it's ok to bathe the baby.
Interestingly enough, when my babies were born 27+ years ago they didn't get bathed at the hospital (3 hospital on opposite coasts) until their 2nd day, they were just wiped down with warm water after being born..
Google "vernix benefits".
This is a link to one of the first entries that comes up. It's actually pretty well presented and cites some research. http://birthbliss.wordpress.com/2010...amazing-stuff/
This might be interesting information to bring to your unit manager(s) or educators, I can't help but think that promoting/providing the information (along with the bathing after 24 hours) might be a good thing. It might help to provide a meeting in the middle with a lot of parents who defer bathing.