It's actually the consumer who drives the economy, not the wealthy. It's simple math.
If you are the wealthy owner of a Walmart, for example, and you get a huge tax break but your consumers don't so they don't have enough money to shop at your store. Your logic says that the wealthy owner of the Walmart will hire more employees due to the mere fact he/she got a tax break. But no one is shopping at your store, so why would you hire more employees to man an empty store? The answer is that you wouldn't.
How many tubes of toothpaste does the top 1% percent purchase versus the other 99%? How many automobiles? How many meals out at a restaurant? How many home improvement supplies? How many computers? How many items of clothing?
The more money the masses have the better off the whole economy does. Henry Ford knew this and so paid his workers an unheard of wage of $5 a day, double the average factory worker pay at the time. He knew higher wages meant those same workers could afford to purchase a car for themselves. His business exploded after that, making profit hand over fist, far more than he would have made had he kept wages down.
Simple math.