Whose historically low tax rates? As long as I've been working it has been well known that when you make more, you eventually jump up to the next tax bracket which has a higher tax rate. [1]

A single person making $10K (taxable income) in 2013 paid $1,058 in taxes... or ~10%.

A single person making $100K (taxable income) in 2013 paid $21,293 in taxes... or ~21%.

If 10 people each made $10K, they collectively made $100K and paid $10,580 in taxes... which is still less than half of what the one person who made $100K on their own paid.

[1] http://www.irs.gov/pub/irs-pdf/i1040tt.pdf

Edit: I did just get my taxes done so I might be a little more bitter about the topic than I usually am. But the numbers suck.