If you want to live in a civilised country with the benefits that come with it, then there is no alternative to tax.
That is the price you pay.
So, no its not theft.
There are a lot of "civilized" countries with zero income tax, such as the United Arab Emirates and Kuwait. That said, I agree that it will be hard for normal countries to abolish the taxes, as they don't have any other source of revenue. But I would prefer less taxes and lower government spending.