"I don't hear any of them complaining about the "extra" work." - Maybe it isn't as overwhelming as what I have listed since most probably manage a few projects at once? Do bear in mind that teachers manage not only a few projects, but at least 50 parents and over a hundred students, some of whom with family or personal issues.

"It's even more absurd hearing some teachers complaining about taking a CCA."

"Shouldn't teachers go into the teaching career knowing that they have to perform both the teaching and non-teaching tasks, and not expecting anything less?" - Hope you will have greater empathy for teachers after reading the insights that I have posted. The non-teaching tasks in schools could definitely be reduced further to allow teachers to focus on quality teaching and learning in the classroom.