Yes, mitigation of climate change is more economic than adaptation, because it is a more practical way to attack the problem. Everyone can participate in mitigation, because it is as simple as planting a tree. Adaptation more or less requires reverting to an older way of life that is less desirable for many reasons.
Stopping global warming is an entirely new industry. Yes, it will cost trillions of dollars to mitigate global warming, but firms can make money off of it just like anything else! Petroleum and coal companies can put more profits into research and development towards greener options and reducing carbon emissions. If petroleum and auto companies had done this in the 1970s during the Arab Oil Embargo, we would already have millions of electric and hydrogen fuel cell cars on the road in America already.