iPod App On My iPhone 4 Uses Data

I was just fiddling with all my apps when I came across this problem. I also managed to replicate this incident. Heres what I did:
-I closed all my apps (completely closed; not in the minimize or multi-task mode)
-I checked my data and it states Ive used 70.1 MB
-I opened up the iPod app, and everytime it does, the icon indicating data is being used always shows up.
At this point, I thought to myself I was just being paranoid. So I closed the iPod app completely and turned it back on. Again, it used up data. I did this for a good 10 minutes over and over again, until I managed to get my data usage from 70.1 MB to 75 MB. It took a while, but at least I know I wasnt just being paranoid. I asked 3 of my friends to do this and they got the exact same thing.
Ive got the iPhone 4 with the latest iOS. Can someone else please verify this?
Windows 7