Gay also stepped on the outside of his lane in the finals. Nobody mentioned it because that is NOT a violation as long as you don't impede the runner next to you. It is also NOT a violation to step on the line on the straight if you don't gain a material advantage or impede another runner. Stepping on the inside on a curve for more than a step is a violation. USATF Rule #163.
Typical example of posters on here knowing next to nothing about track and field.