Whaaaat? How is there nothing normal or relevant about an athlete making healthy choices and an obese person doing the same? Being human is commonality enough. I just saw the episode. She didn't come off as smarmy, arrogant, or condescending. She points out sacrifice and priority as something she has in common with them, which is truth. She also congratulates them very graciously at the end of the challenge.
As far as Subway goes, whatever she's an athlete with an endorsement. An endorsement with a healthy message. Beats being on the side of a happy meal that's for dang sure. Are all their sandwiches gut busters? Probably not. However, Nastia isn't there ordering people to layer 5 cheeses, no veggies, and a 2 inch thick smear of mayo onto salami and roast beef on white bread dipped in oil either. She struck a pretty happy medium between making some money over a brand name and maintaining healthy lifestyle integrity. Subway is literally what the individual makes of it, and as franchises go they are doing more than most are to promote good menu choices.