Finnish has a wry, sarcastic idiom "Kaikkea se leipä elättää."
The most faithful translation I can think of is "Bread sustains all sorts." This one is really tough to translate.
Such an idiom doesn't exist in the English language as far as I know and the translation may not quite capture the cruelty of the original Finnish idiom when the object is a person. The original refers to sustenance as a biological process. The "kaikkea se..." structure ("kaikkea" = partitive case of "kaikki" = all, "se" = it, "leipä" = bread, "elättää" = sustain) is often used to express irritation or surprise at the existence of a particularly wide range of things. Often in a negative sense. The idea here is that someone's mere existence is contemptible.
Not a native English speaker, as you know, but I thought of a couple:
It's a bit like the other Finnish idiom, “Meitä on joka junaan”, which is perhaps a bit more neutral, but essentially means the same thing.
"It takes all sorts/kinds" is positive and accepting. "Even the useless get fed." doesn't exist in the English language but expresses the same as the Finnish idiom. You are correct that "Meitä on joka junaan" is more neutral but means pretty much the same.