Basically, the benefit of Dailies is really rather simple. WoW players need gold, they need it for repairs, they need it to buy stuff on the AH, they don't need quite so much of it now in some ways(you don't really need a mammoth), they always have and they always will because Blizzard needs to pull gold out of the economy or else the whole thing will go pear shaped.

They also need faction reputations at least to some extent.

Dailies are fairly tedious a lot of the time, but when it comes to getting reputation and gold, they are, while not necessarily much more interesting than farming, a heck of a lot more efficient. You do a few dailies you get a few hundred gold, you get a few thousand rep, you're done in a couple of hours.

Compared to the old days of people trying to farm grey drops off the crusaders in EPL it's actually quite an improvement.

Yes it's still boring, but it's boring for a lot less time for a lot more reward(though personally I'd like to see more of a combination of reputations, dailies, instance runs, and the old grind so that players with different kind of schedules can all get rep).