Why does your friend assume you are not going to pay taxes? Consider yourself lucky to only pay 20% on any gain in value. The money you work your butt off for, that is income, likely costs you 30+%.
It sucks that it costs like 30% of your paycheck but what sucks more is the stress brought by overly complicated tax code.
If all 300 million people pay a simple tax of 1000 bucks a year to the US gubernment, they would have something like three hundred billion dollars to work with every year. Very simple tax and plenty of money for the government to run.
Alas, our government is not a lean, efficient machine.
Hundred of billion of dollars are lost every year to inefficient military research program, pointless wars, jails, porks, paperwork for social security, and enforcement cost for the US' byzantine tax code.