Now Playing: 04-16-12 Marketplace Tech Report

April 17 is tax day -- so all you procrastinators out there better get going. While it's easy to dwell on just how much we pay over to the government this time of year, we're actually paying taxes all the time -- when we buy things, when we fill up our gas tank and when we pay our cell phone bills. Those phone bills are the focus of proposed legislation in Congress that would freeze cell phone taxes for five years. But why do the cell phone companies care how much we pay in taxes?