What happens next?

Saw this and many other amazing builds at Chicago Brickworld. Should have asked these guys, but what do they do afterwards with a zillion tiny lego bricks? I suppose they can brainstorm the next project based on their now plentiful supply of gold, red, and green bricks. Anyone can hazard a guess in how many lego required for this build and rough cost? How do they buy this many? This was a huge one. The vast number of gold bricks felt like a procurement flex. Like someone at a pick a brick...