Because of the doubling of gas prices, with flirtations at the $4.00 mark occasionally, we hit break-even at 80,000 miles.
I call B.S.
Let's check your math. Assume an average of $2.24/gal. over the 80,000 miles (that's the average of $1.49/gal. and $2.98/gal., which is twice $1.49/gal.). Also assume you got 50mpg. Total fuel cost over the 80k miles = 80000 miles / 50 mpg * $2.24/gal. = $3584.
I think we can guess that you bought your Prius in 2002. That's the last time regular gasoline cost $1.49/gal. MSRP for a 2002 Prius was $20,000, and I think it's safe to assume you paid full sticker price (Priuses have always been a hot item). We'll keep things simple and ignore any sales taxes or other fees. This gives a partial cost over 80,000 miles of $23,584.
What was the other car you used for comparison? In order to hit breakeven, its sales cost + fuel cost over 80,000 miles must have been $23,584. If you're comparing to a similar sized vehicle with similar features, you're probably looking at a sales cost of around $13000 (the 2002 Corolla for example had an MSRP between $12000 and $14000, depending on features). $13K is probably a good, conservative assumption.
In order for you to really have hit breakeven at 80,000 miles, with an average fuel price of $2.24, a $13000 car would have had a fuel cost of $23584 - $13000 = $10584 over those 80,000 miles. That's a fuel efficiency of 80,000 miles * $2.24/gal. / $10584 = 16.9 mpg. That's horrible efficiency for a small car. I don't think any small car built in 2002 had anywhere near 16.9 mpg. Even the Ford Ranger had better estimated efficiency than that.
Despite all appearances, your boss is a thinking, feeling, human being.