iPod Nano 5G FM-Why Headphones?

[AppleTech22]

So I sold my iPod touch and before that I sold my 2G nano, which required a little FM adapter(at the time made by apple) to listen to the radio. Now with the new 5G I use the built-in radio feature all the time. I noticed also that you must have headphones plugged in for the radio to work, why? If the headphones have anything to do with the radio signal, which I don't think they do, why wouldn't Apple put the radio feature into the iPod touch and iPhone? Or if not, why do we need to plug in the headphones, why can't I go with the built-in speaker to listen to my stations?

Thanks,

AppleTech22

 

[rgarjr]

I think the earbuds cable act as an antenna.

 

[Skwink]

I've noticed any cord works.