There are two different arguments being made on this thread. One is an emotional argument ("Hey, that's just wrong!") and the other is economic. What makes economic sense doesn't always make emotional sense, and visa-verse. I'll ignore the emotional argument.
The root question is: How much money is generated by a given saw chain over the course of it's usable life?
The economic argument pivots on the cost of labor. At a certain point, it is economically more advantageous to replace rather than repair. We all know that. Now, at what point this happens with a saw chain is another question. It's a bit complex. The business owner wants to keep the cost per cut as low as possible. So you have to weigh the material costs against the labor costs. I can see hiring low-wage workers who can swing a saw, but not sharpen the chain. Or having high wage union workers who can touch up a chain just perfectly, but take a half-hour @ $35/per to do it. Or the sole proprietor who doesn't want to pay himself his average hourly to sharpen chain. But let's say your shop will sharpen a 20" loop for $8.50. New Oregon chain is $12.99 (Bailey's has a sale right now). One of your employees has to take the chains to the shop and pick them up. Your workers have to keep the sharp and dull chains separated. Simple, yes, but so are a lot of employees.
Also keep in mind, those dull, but nearly new chains represent a business opportunity for someone else. So before you declare swapping out chains to be a a waste, you have to look at the economics. How much money is generated by a given chain over it's lifetime? Buying new chain makes money for the chain manufacturer, that means jobs. Makes money for the seller, that means jobs. Might save money for the user, under certain circumstances. May create a business opportunity for someone to sharpen and resell those almost-new chains. Would save money for the person buying a good used chain at a reduced price.
Hey, it's not how I do things, but it can make perfect sense.
If you are a homeowner saw user, none of this applies and you should learn to file your chains. But, again, it's your choice.