The $500 buy-in chips are won in satellite tournaments and then used to buy in, in the regular tournaments.
Also
If you are going to buy into a regular tournament with cash say $5,000, you 1st have to go to the cashier and buy 10 of the $500 buy-in chips and then go to the tournament clerk and buy a seat with them. No cash buy-ins accepted for tournaments at the Shoe.
So, the buy-in chips are never in play in any tournament at the WSOP.