Illegal immigrants, like the name implies, should not be in California or anywhere else in the US in the first place anyways, let alone receiving checks.
Of course, the real problem is not the illegal immigrants themselves but the fact that the US has illegal immigrants that have stayed in the country for years or even decades in the first place; and in some cases even have kids who are US citizens.
But that's a reason to introduce a path to citizenship and maybe ease up immigration laws, not to let people starve