Front hub bearing assemblies

I had front hub bearing assemblies replaced in Oct. 2007 at 87,000 miles. The left wheel had to be replaced several months later due to a defect. Now two years have gone by as well as 8000 miles ,and the right wheel hub had to be replaced. I was told that I didnt’ have to pay for the part, but did have to pay for labor since it had been two years. What do you think, and is there anything I can do?

The warranty is for the part only. They are doing what is customary practice in auto repair.

Thank you!