It makes every difference. Not every fan is like you. Some are die-hards. Some come when they aren't working. Some respond to being reminded that games are on. Unless they're reading the sports section of the newspaper, where would they be hearing about the game?
The club, I would guess, could reduce the cost of tickets to offset the NBL levy and make the tickets accessible. You cannot discount the cost of tickets in turning people away!
Don't forget that during the season, people were using 2-for-1 vouchers or buying $15 tickets. Suddenly, come the first final, the minimum adult ticket was $32. "A few extra dollars for a few extra tickets was not a lot to ask." - double the cost isn't "a few extra dollars".
I watch the Crows on TV during the AFL season and I care that "they're striving" to win the flag, but not usually enough to go to the games. There are a lot of basketball fans who'd be the same with the Sixers.