Headphones have some advantages over speakers because they take the room out of the equation, which is a downfall of many systems.
But if you listen to live music, what you hear is more like what a pair of speakers in a room reproduces. Your left ear gets the on-axis of the left speaker, and some reflected/diffused/off-axis sound from from left as well....and the same goes for the opposite ear. This is more natural to listening to live music (which I do basically weekly or bi-weekly, advantages of my location hehe).
To counteract this, a lot of high end headphone amps have what is called a 'crossfeed' or headphone enthusiasts look for software based solutions.
So, no, headphones are not superior in that respect. They give an 'in your head' presentation, versus speakers that have more of a forward presentation.
Another downfall of headphones is the impact. With live music a kickdrum rattles your chest, with headphones that just isn't possible.
That said, I listen to both daily.
I love laying in bed listening to headphones...it's just so personal, so compact, I fall asleep with headphones on my ears all the time. When I fly, my headphones are on at all times except for security and the time they tell you to turn them off during takeoff and landing. So, don't get me wrong, nothing wrong with headphones!