It is. Everytime you hear someone say 'this is good for the economy' or 'our economic growth has slowed down' or 'the GDP has grown by suchandsuch percent this year' they are assuming trickle down economics work. That is because you might have a mental image of the economy being made up of small buiseness owners in your head while in reality ownership of things that benefit from a growing economy is largely in the hands of a small amount of people. In the US for example the top 10% of people own 70% of all of the countries wealth while the bottom 50% own about 1%.
Wealthy peoples' wealth also is made up of investments in company's to a larger extant than poorer people who have a larger percentage of their wealth made up of cash, houses, cars and other such 'real' things which don't benefit from a good economy. This wealth disparity exists in most countries to varying degrees. Globally speaking it's even more egregious.