The whole concept is sort of nonsensical. Tooth paste holds its shape just fine when pushed out of the tube . . . same can be said for peanut putter. Yet these are prohibited items.
Then there is powder, talc/baby powder is a solid, but won't hold its shape, but it's OK . . . powdered baby formula doesn't hold its shape yet it too is OK. Then consider taking a couple or three innocuous powders and mixing them together. Might just be able to make an explosive.
It's all just feel good theater that does nothing to improve security.