Talking about some snakes being more active at night got me thinking...
For awhile, I thought my snake that went blind over the past year had gotten less active, since he was almost always in his hide with just his head sticking out (it was kind of like a turtle; he just pulled his head back in when something walked past his tank). But then I had to spend the night in the snake room when we were painting mine, and he spent the entire night moving around. If I go in at like 3am, he's almost always out, trying to escape from his tank like usual... I think it's because he can't tell light/dark at night, so he doesn't get freaked out by the least shadow that goes past.
Not sure if your snakes have any vision issues, but thought I'd mention it since albinos seem more likely to.

That is a bangin' enclosure btw! They're definitely not being lazy because they don't have anything to explore/climb on!