I use fake plants for several reasons.
1. They're cheap. I get the ones from Wal-mart's craft department and cut off what I need and make my own decorations. Or you can go to a petstore and pay more for already made stuff.
2. They're easy to take care of. If they get dirty, you can take them out, beat them on something to remove dust, and wash them with soap and water.
3. They don't require care and maintenence. I'm sure real plants look better, but the downside is that they require watering and fertilizer.
4. No chance of dirt borne parasites or insects hatching out inside your viv. I tried a real succulent once in my leopard gecko container, total disaster. The warm temps brought out a slew of baby centipedes.
5. There's no chance of your pet digging in the pots or munching on the leaves by accident. Plus in a small confined area, the reptile in question will probably trample the plants down or knock the pots over (if your snakes are like mine and like rearranging their water bowl). If a fake plant gets bent out of shape, you can bend it back into shape.
Here's a picture of my anole cage:
I hope that helps. I think real plants look good for amphibians and they're more functional as well in that sort of environment. But in a snake environment, it just gets more troublesome in my opinion.