Spending capacity of a single person does not scale though. A member of top 1% does not eat 1000 hamburgers in a day because they can afford it. They might spend $1000 on a single hamburger or several million $ on a car but it is hard to see how that money trickles down rather than stay in the Veblen goods ecosystem.

You could say the same of every dollar everywhere no matter where it goes, so that statement is essentially meaningless.

You're right. The problem is that rich people don't spent much money, they tend to already have most of their needs met.

Poor people on the other hand are much quicker to bring their income back into circulation. If you want a lot of money to be spent domestically, you need to redistribute the money to the poor.