If people want to speak up for their own needs, let them. Where's the harm in that? "Bitching and whining" might be your old-school way of belittling by making them sound like women and children, but it really only reveals your own insecurity and discomfort with change...
In a strong economy, skilled workers have more leverage and ought to use it. And yes, if they are unhappy with the response, they can and will leave for other opportunities. That's what intelligent, talented and capable people do all the time.