Actually, a fair number of people get net income from the IRS because they get "refundable tax credits" and the Earned Income Tax Credit. Most tax credits either reduce your taxable income or reduce the amount of tax levied, but in any case, you can never end up with anything less than $0 on the "tax owed" line, so you simply get all of your withheld money back.

Poor people currently pay either no taxes at all or very low taxes as proportion of their income.

The average state and local tax rate on the wealthiest 1 percent of families is ...(snip)... a mere 5.2 percent.
The average tax rate on the poorest 20 percent of families is ...(snip)... 10.9 percent, it is more than double the effective rate on the very wealthy.

Ten states — Washington, Florida, Tennessee, South Dakota, Texas, Illinois, Michigan, Pennsylvania, Nevada and Alabama — are identified in the study as particularly regressive. These “Terrible Ten” states ask poor families — those in the bottom 20 percent of the income scale — to pay almost six times as much of their earnings in taxes as do the wealthy