That's only one side of the coin (to coin a phrase).
Capitalism is equally a system that allows you to sell your labour to the higher bidder even if your current employer (which could be an essential public service) really needs you. Even if you don't strictly need the extra money. It allows you to aspire to a greater level of wealth for you and your family and your descendants (though too often people take a short-termist view of this, leading to disappointment). It allows you to devote your capital, plus the benefits of credit, towards goals which are important to you and you alone, not the state or some commisariat. It allows you to waste money buying goods which therefore brings employment to a host of other people involved in their manufacture, delivery and sale.
Naturally, in a head to head battle with one single employer over rewards, the individual is likely to lose. But you can always say stuff them and re-locate to another city and work for another employer. In fact, you can even set up your own business, and that's where credit will really come in handy. Hard to picture successful business start-ups in a socialist state.
And that's where anti-capitalist sentiments fall down - there has to be something to replace what you don't like, you can't simply destroy it and leave a socio-economic vacuum. And socialism or at least a form of managed economy is what normally steps in. But at least they leave everyone's lives equally impoverished, so I guess that's fair.