As was said long ago by Justice Pitney in Coppage v. Kansas, "it is from the nature of things impossible to uphold freedom of contract and the right of private property without at the same time recognizing as legitimate those inequalities of fortune that are the necessary result of the exercise of those rights." So why uphold this combination of property and contract rights? Not because of atavistic fascination for venerable legal institutions. Rather, it is because voluntary exchanges improve overall social welfare.
Three Cheers for Income Inequality