Every dollar of income tax taken from a poor person is a choice of which necessity to go without this month.
I've come to the conclusion supply-side theory is bunk. Give a poor man a hundred dollars and he'll spend it. The drug war has proven that if there are people with money to spend, someone will do what it takes to supply that demand. If someone crunches the numbers and decides it's not a good risk to start a business, instead of subsidizing the supply how about we subsidize the demand?