You can't reach the plug from your seat? Hmmm...
I do, however, agree that leaving the company headset unplugged is not very sportsmanlike and can make one feel a little peeved!
Measured db level recently (albeit on an iPad app) and it hit 80db in the cruise.
I was told that engineering (at our airline at least) will 'approve' or 'certify' your own headset for use in the flight deck.
Therefore I am interested in any answers to the OP...