The card quality and tutor effects are simply much more mana efficient so unless the combo deck has alternate uses for the specific draw spell such as a discard outlet or recursion effect it will avoid the latter in preference for the former
The static ability is what its here for
7 Shroofus Sproutsire Doesn't Leave Mushroom For Other Creatures While Shroofus fits nicely in any existing Saproling deck, he also works very well as the commander of his own build, too
Despite this it tends to be the blue decks that play it as it is such an effective way to bolster your early game when you lack low curve cards which is something blue struggles with more than the other colours in Magic
(It's an artifact with ", , Discard a card, Sacrifice this token: Draw a card.") Sacrifice two Blood tokens: Transform this creature
We will get the cards from Storm Emeralda in our English Delta Reign set on November 6th -- a whopping three months after Japan