This isn't about who works the hardest, but I would say that my contract as a teacher is a bit different to any contract I've had in industry.
Basically, our contracts specify "directed time" of 1265 hours over the course of the year. This is time where our school can tell us (essentially) where we should be and what we should be doing. This is supposed to cover all meetings, evening events etc as well as (obviously) our teaching hours.
Then, on top of this, there's an expectation of working additional hours to plan/mark etc- but the idea is you can do that at home, and whenever you like, so e.g. I can come home, cook dinner and then mark from 7-9pm or whatever, or I could save up the work and do it on Sunday if I prefer that. I agree that this is, in many ways, similar to a lot of professional jobs.
The directed time, which is when the school can tell us to e.g. be at a parent evening or open event- i.e. you must be in school until 8pm this Friday- can become a source of dispute because some schools like to have lots of meetings and events and this can push people over. You might argue it's a non issue, but our pay is specifically calculated around the 1265 hours. If a lot of schools think it's not enough, then I think they should change our contracts to increase these hours, and then also increase our pay accordingly.
As a separate point, some teachers do get confused by this and think they should be able to get everything done in the 1265 hours, which was never the intention.