That is really weird, is there any reason to use them other than repeated removal/reinsertion? (Hence found on chip programmers, component testers, etc.)
ZIFs are on our test board for our breadboards kit schematics – they are used (as you have mentioned) to insert/remove chips for testing. And fast check of ROM firmware for it's updates.
So we've built a test PCB board to test fast our chips and schematics.
