Because the dailies are not just daily tasks. They have backstory and context.

SWTOR for example moved toward more and more convenience for their "Heroics" (dailies) to the point where you can just pick them all up from a terminal on fleet and port right to the location. Completely devoid of the context that was originally there -- who the questgiver was, why they are actually sending you there, conversations that your companions can actually chime in on, etcetera.
A LOT was lost.

Secret World Legends also has dailies in all zones scattered where they are contextually relevant and no convenient instant port. It works better, people actually go to the zones to pick them up and do related stuff there, and no one complains about it.

At least they put the questgivers where you can't be attacked while talking to them, not like in Cyrodiil.

AlnilamE wrote: »

Getting one, completing it then going back to base through the sewers to pick up another one is both risky and time consuming.

I suspect this was so people can't cheese that safe zone. So you couldn't, like in Cyrodiil, just go back into a town's tower where you first arrived by Transitus. It's not relevant that you can run back there in CyrodIil because the flags to capture the town aren't in that tower and the map's so open you can approach the town in many ways. But in the IC you can shoot from that platform; and you need that protection so that people can't just sit below the platform and camp your arrival point. But once you go down, they probably don't want you running to it as an easy escape all the time.
Instead, now people go through a door in the IC and stand in the safe zone while queuing Cyrodiil to get out.
Pretty lousy design just because people would exploit a ladder back up to where you arrived from the sewers. I bet they actually had planned for a way back to that safe zone but realized it would be cheesed one way or another because it is silly that you can't go back that way you came.