I think because they want to make a difference in life.
Their solution works, but in the most horrible of ways.
It is very possible, that a rock could have changed the course of the Colorado River millions of years ago.
Its hard to imaging what Las Vegas would be like now if it did.
The Twin Towers attack did change the world. Its sad to say it, but our world today would be different if it hadn't happened.
And if you like your world as it is today, then that tragedy was necessary.
For the present to exist as it is, everything good or bad had to have happened exactly as it has happened.