i dont do it because:
then i dont have to separate them to feed

i can keep track of a snake that is not drinking

if one should happen to regurge i only have to worry about one snake and not which one was it.

so i dont have poo smeared everywhere

so if i have a runny poo in there i know what snake it came from

i really have many reasons, you guys do what you want im going to keep mine separate.