The Universe is uniform because the enormous expansion during inflation smoothed out the wrinkles in the spacetime fabric, much as stretching out your jacket sleeve eliminates the creases in its fabric.
I would have expected that a dramatically expanding universe would increase the size of any tiny idiosyncratic clusters. Much like when you fill your jacket sleeve with explosives, tiny imperfections in the fabric become massive gaping holes.
I just don't understand. Much like how a jacket sleeve doesn't understand.
Also, the jacket sleeve analogy doesn't help at all.