Because America has such a poor social safety net that it is very easy to go from well paid to homeless in just a few years. Accordingly, everyone is fighting

Because America has such a poor social safety net that it is very easy to go from well paid to homeless in just a few years. Accordingly, everyone is fighting to make enough money to not get fucked over during each of our cyclical "economic recessions". During each recession more and more people permanently fall into poverty and everyone who is left fights even harder to not be a victim the next time the economy goes south.