I think S&B don't want it flat, because the implication would be that it is safe to stand it on its' own, and it is not. It needs a broader base to support it properly and I think they just wanted to keep the lines slimmer, a little bit more pocketable. When passing with my friends, one of them will put it down and expect that this balancing act is okay. Mine has face-planted from this position and come away with broken fins near the bowl.
Some folks like stands that slide on firmly and pretty much leave that on. I prefer the one from
@Ratchett that doesn't grab on, you can lift Mighty in/out easily and it weighs next to nothing. I got mine in 'glow-in-the-dark'. Imo, S&B could include something like this in the box (orange!) with the other plastic accessories. Wouldn't be the first time they got an idea from delta3dstudios!
The smaller Crafty has flat bottom, but it is much shorter with a lower center of gravity.