Dark matter/dark energy work in the existing framework of GR and align well with observations. That's why they're so heavily favored. It's simple. Saying the l

Dark matter/dark energy work in the existing framework of GR and align well with observations. That's why they're so heavily favored. It's simple. Saying the laws of physics may be different in different parts of the universe is a statement that so far can't be substantiated, and we've been trying for over a hundred years now, is far more problematic. That's a dire option that we don't desire to pursue unless we're absolutely forced to - and we're not being forced to. Between the two options we're going to stick with dark matter/dark energy until evidence suggests otherwise, or until a better, and simpler, idea comes along.