Because we get payed based on perceived value on the market and not based on utility, importance and certainly not based on positive impact. All of these things are incredibly hard to measure and I don't think there is a reasonable objective way to evaluate them.

The more people are willing and able to do a job, the less is the perceived marked value, especially if they are not organized in unions to assert their interests.

Now from what I know unions are generally frowned upon in the US for some reason or another (perhaps because of their obsession with capitalist ideology), and reports say that large corporations are actively oppressing the formation of unions.

So what is left is simply trying to avoid work and perhaps hoping that some companies will come around and provide reasonable working conditions and pay or to start businesses themselves, while trying to survive the bullying tactics of said companies.