Why are you guys accepting it?

I just saw a post from a PhD student getting a 19k $ stipend in the USA and read many comments of people getting similar stipends. COL is generally quite high in the US (healthcare, rent, almost no public transportation, so one needs a car to get around, expensive groceries and so on) compared to where I live (Germany). I get around 33k€ after tax and social contributions, but according to ChatGTP that provides me with a similar standard of living as getting 55-65k $ in NYC or California/40-45k $ in more affordable US regions. Now I'm wondering: why are you guys even doing your PhD if it means living in poverty? Why not take your bachelor's or master's degree and find a job?