What you are describing is a toe out condition. The front of the tires are farther apart than the rear.

I'll bet your steering is twitchey fast. Tending to pull either left or right and with little or no tendency to stay on center. The tire wear and the twitchey steering go together.

You said your steering wheel was replaced, did you intend to mean that the steering box was replaced? To accomplish that replacment, the mechanic has to dis/re-connect the rods that attach the wheel spindles to the steering box (tie rods). That will impact the wheel alignment. Except that a competent mechanic knows to take care of that.