Nop, it isn't. Sleeping in Baldur's Gate had a purpose that involved content that would happen specifically while camping outside cities.
This wasn't an MMO and you cant have scripted stuff to be done every time you fall asleep, eventually its going to be boring.

In digimon world, pooping was part of the evolution chain mechanics, changing the evolutionary branch
I dont remember the digimon to have to poop in order to evolve in the anime series, it was in the game because they made you believe its needed, your creatures could evolve by using a system that is fun.
Also FFXIV is not a pet sim and digimon is not an MMO.

This is what i mean...you having a purpose behind the mechanics...not just having it for gil/time sink. They're slightly different.
I fail to see the purpose.