They contribute a service, in this case a search engine that's miles ahead of its closest competitor, Bing. They don't "take" anything, they offer something that you're free not to use. Unlike nation states, which are happy to take whatever they want (claiming they're owed it for providing you things you may never have asked for, which are paid for by other people potentially against their will, and for which you're probably not allowed to solicit alternative providers) and your only option if you don't like it is to emigrate.
Google doesn't throw black people in prison for recreational drug use, Google doesn't prevent people from marrying who they want, Google doesn't send people to die fighting pointless wars in the middle east, or drone bomb weddings.
>but if I have to pay company tax, why don't they
If you're uncomfortable with how much taxes you pay, then blame whoever's taxing you, not Google.