One guy makes 90 grand and pays $6000. Another guy makes 150 grand and pays $9000. Both guys collect the same amount on retirement. Is that fair? If the guy making $150000 is self employed he pays $18000. but still receives no additional benefits. Still fair? BTW US congressmen earn a little over $150000 and pay nothing into SS. Is that fair?
Well, it is a form of insurance - it is presumably possible that the high earner may fall from his enviable estate later in life, but before retirement. It will be nice for him to know that he always has social security to fall back on. And if he doesn't fall, he is lucky.
Of course in all seriousness we do know that most people making $150K are members of a class that is likely to continue to make in that range, while people who make 20K are extremely unlikely to make more, but in theory social safety nets are intended to protect everyone from misfortune as well as structural inequality.
