My Ana Gwyn will drink water while I'm holding her, almost every time I offer it. She's always got fresh water in her tub, in fact I use a plastic dog dish and it doubles as her favorite hide. She drinks while she's in there, but she'll also drink while I'm holding her without hesitation.
I figure it's a case of "snakes are weird."
Certainly sounds like it .. I know of some who love absolutely fresh water but I’ve seen many reports of people who have NEVER seen any of their snakes drink ever ..