An employer would rather fire what he considers to be extraneous employs as productivity rises than give all of his employees fewer hours at the same pay, ostensibly for the purpose of remaining competitive. It's crap, but not a whole lot can be done about it.
And it only happens because the system makes most people desperate for employment. The only way to remedy that would be through government regulations.
In a system where productivity rises and pay and leisure do not (or actually decline as it has for most Americans since 1980), staying "competitive" ultimately just hurts businesses in the long run because the increased productivity will create excess supply while demand remains largely the same. This drives prices downward and further encourages employers to raise productivity and thin out their workforces in a race to the bottom.
When the capitalists at the top of the pyramid relied on human labor to produce the goods that they sold, it was easy to redistribute wealth. Now an incredible amount of wealth is gleaned off of non-human labor (with computers/robotics/or simply making money off of money)... and that all concentrates at the tippy top.
Ideally, in a society where technology supplants human labor, people would be paid more and more for doing less and less work... thus enjoying the fruits of innovation and technological advances until eventually much of the economy is automated and we find better things to do with our time with all of the wealth we've helped create.