One thing they told me when I dabbled into computer science back at university was that 80% of the bugs only take 20% of your time to fix. That's why sometimes you see issues persisting for very long times, not because the devs are lazy or incompetent, but because there is usually a priority list of problems, with the severe-but-easy-to-fix ones always taking precedent and the not-game-breaking-but-difficult-to-solve problems being last line.
There are two parts of the quest chain for each continent. The first part involves defeating numerous Master Pet Tamers, and the second requires you to triumph over the Grand Master Tamer. After you've bested the Grand Master Tamer, dailies from each Tamer will unlock for that continent. All the dailies continue to reward experience for your companions, however only the Grand Master daily quest will reward the Sack of Pet Supplies.