I have a call every morning with my team in India. Because of time zones, that call is every morning while I'm on the train. I can't hear anything with regular headphones, and you wind up having the volume turned all the way up trying to drown out the ambient noise. With my Bose ones, I can keep the volume relatively low, and hear the conversation extremely well.
Plus, when I'm not on a call, being able to put on some quiet music and not having to hear the sounds of the subway, the train, the guy on the train listening to music on his cell phone without headphones, stop announcements etc is great. That alone is worth the cost of the headphones to me.