Teaching is more demanding than many ostensibly demanding jobs. You are living by the bell and performing several hours a day to a not-necessarily sympathetic audience. In addition you have to keep up an 'adult' business life of e mails, meetings, professional development etc. You get very little autonomy over your own time. And all this for less money (in many cases) than a London tube driver
However, it can also be very rewarding and a lot of fun.
Bankers, for example, are also at the mercy of emails, bosses, clients etc but they can pop out to lunch or the gym, and they are paid a hell of a lot more.
I think what annoys teachers is when they are treated like servants, which does happen, in a way in which no other professional gets treated (yes I know.,.we could debate whether teachers are professionals, but it would be tedious).
Parents have to realise that education is a joint effort between schools, parents and the learners themselves. If they never sit around a dinner table with their children teaching them the value of education and intelligent debate, the school will always be fighting an uphill battle.
Having said that, I find 1/10 parents to be unsupportive and the remaining 90% are lovely.