Not every hour just the time you spend on class work. Besides everything you pay for in life has a value to it by the hourly rate .. or by the gallon or by the minute etc etc.
You're paying for that time for that class you're paying the University and that prof to teach you. Now if you want to waste the time by doing frivolous things don't gripe about being late on stuff and expect people to be sympathetic to it . Say this was reversed your prof just decided yeh um i didn't want to teach today so hear is a meme, then gripe to you they have to much work. YOU would be heading to the deans office or to there chair saying you want your entire money back because you feel your not getting your moneys worth.,.Just pointing it out