Part of it is loopholes, but an equally big part is that we tax the way the rich earn their money differently. Most working- and middle-class earners make their money from a wage or salary, which is taxed as income. However, the rich make almost all of their money through dividends on stocks, low- or no-interest loans backed by assets, and selling stocks through the market or companies (that they have a seat on the board) doing stock buybacks. All of the income made from the above are taxed differently as “capital gains tax,” which is usually taxed at a much lower rate than income.