That's not exactly true. The USTA does give them a certain number of tickets to events, including part of their allotment for DC matches that are held overseas, but it is up to the netheads to pay for their own transportation and lodging at these events. They are given some tickets to the US Open, but if you look carefully during the matches at Ashe, you can see that they are definitely in the upper tier of seats (but not the very top).
And your USTA membership dollars are paying for trips to the Dominican Republic and other exotic locations for staff retreats and annual meetings. Don't you ever read Wortheim's columns about this?