Benefits vary based on income, but they're heavily weighted toward the low end. So, a poorer person will get lower benefits, but their benefits will be a greater percentage of their income.

Doing a fast calculation, someone who earned $25k (this year, not every year with prior years taking into account how earnings change) would probably get about $14k/yr in social security. So, it isn't a huge amount of money, but it would bring it up.