Maybe Roche figured that few people would actually BUY a disabled meter. Maybe they didn't realize that people could figure out how to use a second strip, placed where the blue strip guide would go, to defeat the interlock switch.
Unless a person is actually shopping for a meter, they wouldn't have found these 'disabled' meters. And, perhaps, many of these 'disabled' meters had cosmetic flaws, cracked displays, or other things that made their sale on eBay (and elsewhere?) a bad idea.
I wouldn't be at all surprised if a large percentage of these 'disabled' meters never made it to eBay or other sites. (I wonder if any of these meters made it into places (maybe Third World countries, for example), where they are badly needed, but their price makes them prohibitively expensive. Or, maybe, provided to people who can't afford new (or most used) units but for whom regular testing was important (and, perhaps, even providing strips that were soon to expire and couldn't be sold). Wouldn't that have been nice?