On the other hand the most dedicated will stay. Assuming employees being equal in other respects it will be good for the company in the long run.
Consider a great engineer, one that can innovate, be a leader, inspire others. If he one day realises that he is not the best he can be while he spends 2 hours commuting every day, and therefore moves to another company where he does not have face obstacle and can focus more of his energy at the problem at hand, does it make him less "dedicated"? To whom?
I think you are confusing dedication with something else.
And assuming employees being equal in capabilities I regard the ones unwilling to take this extra burden as less dedicated than the ones that accept it.