Yes, in a democracy, we allow people other than the government to make decisions, because we understand that the proper scope of what should be voted on is not "everything."
I don't think you're recognizing a critical distinction between the type of decision being made.
The difference here is that a job offer or an investment is a decision made by an employer or an investor. US citizenship or work/residency, on the other hand, is a status not with an employer or an investor but with the US government and the citizens it represents.
