If you are strong, you may not feel the need for similar wages or a strong safety net. but:
1. Are you sure you will always be strong?
2. Are you sure that all your friends will always be strong?
3. Are you sure that all your children, parents and other relatives will always be strong?
On an individual basis, happiness and success is a game of chance, but this can be countered and almost wiped out by societal solidarity with the currently weak.