the exception of freeroll tournaments, all tournaments
require players to pay both an entry fee (a relatively
small number that goes to the house) and a buy-in
(a relatively much larger number that creates, or
helps create, the tournament prize pool).
Entry fees alone usually cannot justify a B&M
cardroom's expense in advertising and running a tournament.
Normally, whenever a cardroom runs a series of major
tournaments, its side action (money games) increases
substantially in both size and number, and that's
where the casino makes its real money.