1) money
2) time
It costs money to get access to the good you are consuming, and hours to unlock the value. Whether or not you enjoyed reading Moby Dick, you have 16 less hours in the time bank.
If you do enjoy it (I did not), you have paid 16 hours out of the time bank and reaped the reward of 16 hours of pleasurable reading.
There are “cheaper” thrills. I am told you can spend 5 minutes on TickTock and receive some quick gratification. The up front cost is low. The cumulative payoff of spending 16 hours watching cat videos may not be as ultimately rewarding to you as plowing through some classic literature.