Tax revenue is necessary to maintain a functional government. When the government doesn't get enough tax revenue to pay for the things it spends money on, it mu

Tax revenue is necessary to maintain a functional government. When the government doesn't get enough tax revenue to pay for the things it spends money on, it must either increase taxes on everyone, or borrow money from other people to finance its programs. Either way, everyone else ends up paying more in taxes. That's why people treat taxpayer money as "their" money. The government could choose to spend less money and avoid decreasing the tax burden on everyone else, but then the services everyone receives would decrease, and only those who don't pay as much tax would benefit. If we hold spending constant, someone who doesn't pay their fair share of taxes is increasing the tax burden on everyone else.