How is capitalism beneficial for the average person if the capitalist gets wealthy off your labour?

[KM]

If the capitalist owns the tools to produce goods and services, he has power to hire you, and given that you do NOT have the tools to produce your own goods- because that requires money & capital- you must accept the terms the contract in order to sustain your life. (You can choose between similar contracts, but none give you entire autonomy of your labour) The profit is taken from the surplus of your labour- the wage you get is not the entirety of what your labour produced- so the capitalist profits from owning the material you use to produce goods/provide services, and admittedly taking a risk with the capital & labour BUT the vast majority of the profit should go to the workers. So how is this beneficial relationship? It's good for those who own capital but not for those who do not.