It's imputed because the company claims that your base is your "Place of Business"...where all of your trips start and end. Actually, for some bases, your base is your workplace, but for other bases, like JFK, your Gateway or your home is your workplace...where your trips start and end. The company doesn't want to try and figure out which bases are actually where trips start and end, and which aren't.
We have the cost of commuting imputed because we are the ONLY aviation organization that has pilot Bases AND Gateways.
At DAL, your base is where your trips start and end.They don't pay for the commute, so there's no imputed income. For companies like Kalitta, which are home based, your trips start and end at home. Since Atlas has Bases, AND they Gateway you to/from your base (part of the time), it is a company paid benefit that they pay for you to travel (commute) to your workplace...your base. It is like when a company lets the mgmt and/or family use the bizjet for vacation...the cost of the trip is (supposed to be) imputed as income.