He probably did include the cost of new breakers in the price, but he probably did not intentionally "rip you off."
The age of the breakers should not be a safety concern, as long as the new panel lists them as acceptable.
The biggest cause of breaker failures, IMO, is by regularly using them as an on-off switch. Most breakers are not rated for use as a switch. But even that should not create a hazard. If anything, you'd probably see it trip when it shouldn't.
If the electrician did a good job that passed inspection, I'd forget about this.

If he was recycling breakers you already had, that's entirely appropriate. As pointed out, a breaker typcially will last a lifetime. If he brought in used breakers and sold them to you, that IS problematic.

And depending on the age of the panel and how popular that type is in your area, new breakers can be harder to locate.

There is no reason NOT to re-use the old breakers in the same panel, or even move them to a new compatible panel in the same house.

He may well have looked at the old panel and based his bid on re-using the breakers there.

As ronnatalie noted, selling used breakers as new is a big no-no.

Even using used breakers and selling them as new to a different customer is a bad idea.

A CB with 'SW' marked IS suitable as a switch.

No SW, not suitable for routine use as a switch.

When I mentioned the possibility of re-use to my electrician advised me to use 6 new breakers associated with new AC equipment circuits. He said, "why risk expensive new equipment on old breakers?" I did not give it a second thought.

I am in a very different position than you are. My panels are old, groady, and corroded because they are located outdoors in a humid climate. I expect it must affect the circuit breakers too. I envy the condition of your "old panel". Excuse me while I go and cry.

The top panel is a GE, the bottom one is a Square D QO. Both are still in production and you can get the breakers at the home centers even. Even goofy things like old ITE Pushmatics and Sylvania/ZINSCO can be had at legitimate electrical suppliers. Now I gave away a whole panel full of those Zinsco breakers (including 60A I had just bought) to my neighbors when I finally decided to rip it out and put in a larger QO panel, but I'd never had sold them.
It's not legal, professional, or proper.

"He said, "why risk expensive new equipment on old breakers?" I did not give it a second thought."

You should have.

He likely made a nice markup on every new breaker.
Unless you have overloaded the circuit and tripped a breaker multiple times (it can damage the contacts) they failure rate of them is very small.

There have been breaker failures, but those breakers started out bad from the start.

Did he verify each new breaker was operating correctly? Other than turning it on?

Thanks to everyone for sharing their opinions. brickeyee - he did not take re-using the breakers into account for his bid, because at that point, no work had been done and we weren't aware that the first electrician intended to move so many of the wires to the new box. I believe he moved them to new breakers because the new box ended up where the old box had been located and the wires reached that location.

I know that breakers aren't terribly expensive, but it still feels like we ended up with used products, even though we paid for new.

But I do feel reassured that the quality of the breakers should be equivalent to new breakers, even if cosmetically they aren't the same.

I do appreciate those who take the time to comment!

"Did he verify each new breaker was operating correctly? Other than turning it on?"

I don't know. What I can say is that he got the highest recommendations from a building tradesman that was my next door neighbor before the flood. He said that, of all the electricians that he'd worked with, Brian is the guy he wants doing his electrical work.

Shortly after he arrived to do the first work I asked him to do, service panel/meter pan replacement, consolidation of two sub panels from clothes closet locations and about a dozen new circuits, he asked for a broom and a dustpan. I mentioned that to my mom who was visiting at the time and she responded by commenting that she noticed that he wiped his feet when he walked in. Is tidiness and indicator of good work in other aspects? I think so.

In subsequent observation of his work, I noticed that he worked pretty hard to get some stuff just right. Once I suggested that he just give up and just leave the cable be even though it would look a little sloppy if anyone ever saw it which was unlikely. He had bid the job and was not doing it by the hour.

$15,000 in HVAC
$350 in electrical work +/- $30 in breakers

I am sure he made a bundle on the breakers.