Yup. I haven't tried to non-rev any significant distance in the States in about four years. The one exception I found was a December weekend right after the Thanksgiving travel push and three weeks before the Christmas push. I can't think of another good time to try standby travel.
The ex-wife just took the kids up north to visit her family. They started Saturday at 5:30AM, couldn't get on two flights to ATL, went to LGA, bus to JFK, and then a commuter to BDL where she had a rental car waiting to drive another few hours to a lake. A whole day affair for what should have been a three hours flight time plus the drive. And she has a 1998 hire date traveling on her own airline.
Purchasing advance positive space tickets is the only way to go. You'll end up spending more on hotels and rental cars when you get stuck trying to go standby then buying a ticket.