That if there's no such thing as a overpriced tutor then there's no such thing as a underpriced tutor...
In my humble opinion the only person that should be asked about hiring is the tutor itself... If a tutor doesn't want to be hired that should be respected... as for the pupil, if you do not want your tutors to be hired, make sure they want to stay with you... There's so many "please hire me" on world chat that it's normal for people to hire other peoples tutors... Whats the use of a pupil having on his status "don't hire my tutors" and the tutors are asking to be hired????
Like it or not it's a free market... Everyone can get hired... It is clear that if you see a extremely overpriced tutor and you hire it anyway you are looking for trouble... The same way that if you see an extremely underpriced tutor, it's because you don't really care to keep it.
With that said, this is a "war" game, and strategies are part of it. Some people chose to play the game by farming actives, others by farming unactives, others by trading tutors, and others by just being around... Every way is a legit way, and no one should impose their way of playing...
And to conclude my thought I'd just like to say once again, only the tutor should be asked if they want to be hired... If the pupil doesn't want the tutor to be hired, just make sure that your tutor won't want to leave you, and that no one would want your tutor...