You "don't think it's unfair for them to 'give a little of that back to the country that helped them'"?
What is "a little bit," exactly?
Year after year, we see that the top earners not only pay more in federal tax dollars, but they pay a higher percentage of their money in federal taxes. And, not only this, they pay a higher percentage of total taxes.
It's absurd to imply, which you have, that the rich in the U.S. don't "give back."
Personally, I find the notion of one "giving back" absurd, especially when that one already pays plenty in taxes.