LU, their jobs are worth what their employer and society is willing to pay. Since you are talking your about frum teachers, it would appear that your argument is with the yeshivas that underpay them.
You’ll forgive me if I don’t accept your definition of work or what is beneficial to society. Movies are an art form, and like music, they benefit society. Sports, playing or watching, is a form of relaxation that many enjoy and, as such, is a benefit to society.
We live in a society, both frum and not, where every feels entitled. Being a teacher and a hard worker is great, but doesn’t entitle you to anything more than your employer is willing to to pay or what the market will bear.
You are certainly entitled to your opinion, but, in the end, it’s your opinion