No one has spoken about CD cost yet (at least not anyone with experience in the field), so here goes:
The 2 CDs, without Jєωel cases, are only about 25 or 30 cents each. Possibly less.
Even the minimum order of 1,000 CDs, with all the fixins, comes out to around $1100.
That includes a 2-sided, 4 page full color insert, Jєωel case & tray, assembly, and the CD itself.
If you just want the CDs, it would be much cheaper.
And as you might guess, all the work is setting up the machine. The 2nd 1,000 CDs costs the factory much less time & money than the first 1,000 -- and they pass a lot of that savings along to their client.
The SSPX obviously ordered more than 1,000. And they didn't spring for a Jєωel case. Oh, and that lack of Jєωel case makes the CDs weigh only a couple ounces. That saves on mailing cost.
So they didn't do a bad job economizing. Like GGreg said, the "retired" set DEMANDS a physical format (rather than something online or digital), and these folks are retired, with 40 years of work under their belts, often with nest eggs, and are trying to help the Church and store up treasure for heaven as they feel Death get close to their subdivision, if not their front door.
So just one "hit" pays for hundreds or even thousands of "misses".