They can? That's a new one to me. I've put wet snakes back into tubs lots of times and never had an issue. Plus, people with humidity challenges regularly mist the enclosures and wet down the snake.
So long as you're not bathing your snake in COLD water and/or leaving it exposed to cold ambient temps for a long period of time....and so long as the enclosure temps remain in their proper ranges, it shouldn't matter.