You guys are missing the point.
1) When I (for one) have to listen to what one of my friends is saying I have to remove ear buds and listen to him (in most of the cases, I forget to reach out for my cell/mp3 and turn it off, thus waist my battery)
2) Even when you have the button on your handset to answer your calls, it's not enough when some one from the "outside" addresses you. Will you be able to hear him with such headphones? Not really, you'll still have to remove them out of your ears.
3) I wore so many headphones and this style almost never hurt my ears, big headphones always hurt my ears, the ipod (non in-ear) headphones are strong but not strong enough to isolate external sounds, thus make me crank up the volume, which in turn damages my ears. This type of headphone are easy to wear, come in 3 sizes (S/M/L) and do a good job for isolating external sound.