Take rent vouchers: only some people who "qualify" actually receive vouchers because there is a cap on the total number the government gives out. Or the EITC: to get the full benefit your income has to land in a narrow band. Or SNAP: all sorts of weird restrictions, and tons of people who are eligible but who don't know to sign up
But SSI benefits count SNAP as income and there is a dollar-for-dollar downward adjustment for every increase in SNAP.
So if you have SNAP, your SSI benefits will _decrease_ with an _increase_ in cost-of-living!
(Am I here to answer stupid questions...)
It's not actually "large" in the sense of total spending relative to other counties.
So, yeah. Lots of safety nets, all of which require you to live in extreme poverty to qualify for, and which still don't equate to a reasonable standard of living.