For ease. I like the Sig Pxxx series. I've heard the Glocks are easy, but I've also heard that they require the user to pull the trigger as part of the stripping process. I don't know if this is true, but if so it appears to violate rule 1 of firearms safety.
Yes, that is true. When you fire to slide lock or unload the pistol, the striker ends up in the cocked position. You need to decock it to field strip it, and the only way to do this is to pull the trigger.
I'm not sure how this violates Rule 1 any more than the practice of dry firing.