Ball pythons have evolved to deal with life inside cramped burrows underground ... they make them feel safe. Large open cages can really make them feel insecure and can potentially cause stress, health problems, and fasting.

Large cages with lots of "stuff" in them are also way more difficult and time consuming to clean. Health wise, it's better to have a small cage with minimal contents that can be quickly cleaned than a large heavily decorated cage that takes an entire day to break down, clean, and put back together.

-adam