This has already been explained by Rex.
There are apparently nightclubs etc. that have been signing up to iStripper and just downloading the previews to run on their TV's for free. They could run multiple preview clips all night without ever purchasing a card. Not to mention public broadcasting issues.
Now, these clubs would need a person to monitor the whole process and update it constantly, all night, every night. That means employing someone for that sole purpose. Some places might still do that but I'm guessing that they are now a heck of a lot less than before.
I now believe that this was a great move by Totem against piracy and *****. In fact, they could even drop the number to THREE playable previews to make it harder. I would not be bothered by that 😇