...Probably not too far off base... Materials are often the cheapest part of the job... People often underestimate the time it takes, this is especially true with potlights, and if you want a per unit pricing (as opposed to time and material) it makes them weary because there can be unforseen circumstances which will increase install time, they need to try and factor all this in because nobody's happy when they're told it's going to cost more once they've been given a number... They have no idea what's behind your walls or the state of your electrical system, thus they usually try to err on the side of caution (nobody wants to work for free).
Here's an example scenario. Say it takes 30-45 minutes per potlight. (you need to include the time it takes to measure things out, making sure proportions are correct, checking for obstructions, cutting holes, running wire between lights, etc, etc.)
Then you need to consider the time it takes to install the switch and the feed, divide that by the number of lights you have and add that to the time it takes to do each light....
you'll probably end up with somewhere around $80/hr (what the customer see's)
then all the other costs... taking out a permit, insurance, ect, etc...
he's probably pocketing (hopefully) somewhere around $30/hr.
Would you consider that absurd?
Many electricians also aren't crazy about customers buying their own materials because it's possible the customer went as cheap as possible (not saying that's what you did) which could result in longer install time (cheap or flimsy hardware)... Many have a favourite brand, which will allow them to move more quickly because of familiarity and less fidgeting... Again, not saying this is the case in your specific situation.
Another consideration, sometimes they can get significantly better pricing from distributors (when they supply materials) because they have an account with the supplier who will discount based on volume per year... Which they obviously mark up and take a percentage of, but customers still might end up with better overall pricing than if customers purchased material and labour separately.
...that's all I got. lol. there's a saying in our industry... If you think hiring a good electrician is expensive, try hiring a bad one.