And preferrably, in the Material Plane, where the important things happen).
And finally, Anthraxus was renamed Phraxus in late 3e FR and 4e because of the anthrax scare in the nws? Really? Seriously? That's hands down one of the lamest alterations of D&D lore ever. Words cannot describe how absolutely appalling that is. Please tell me that was a legal decision rather than a design team thing.
I mean, this is the game that gave us pistol-packing anthropomorphic hippopotami... IN SPACE.
You mean the yugoloths weren't created and work for Tharizdun?* That's why they are so reveiled.
...
* (specifically my campaign and since 1st edition, no canon here)
That's up for debate, and highly dependent on the type of campaign you're running. If you're running a low level only game, clearly gargantuan dragons are of little use to you. But that doesn't mean the game shouldn't keep them. Same thing with a lot of outsiders who may or may not have even a remote interest in the prime material plane. The 'loths
That said, I could see giving the 'loths a more defined angle when it comes to the prime material since they've always been largely consumed with outer planar politics and long-scale manipulation of events there. For instance, we know the 'loths abhor gods virtually above anything else. If you posit that the gods created mortals (in and of itself also very up for debate), the 'loths might likewise despise mortals as well in some capacity (though not on the scale of Pathfinder's daemons). And since the 'loths don't rely on mortal souls to create more of themselves like devils require and demons do as well to a slightly lesser extent, the 'loths don't care if they muck with affairs on the prime material plane, screwing both with its function as a soul factory for the other fiends, celestials, and the gods. Let the 'loths tinker with the affairs of gods and men, not just pull the puppet strings of the other fiends?
Re: "important things happen in the Material Plane": we can all agree that the vast majority of campaigns happen in a Material Plane, and the most important events of those campaigns are the actions of the PCs. So what I meant is "why do I use daemons to meddle in PC affairs, when I already have demons and devils for that?"
"From a mortal's perspective, what makes them different?"
From a mortal perspective what's the difference between a village ravaged by orcs or gnolls or hobgoblins? It's up to the DM to decide.
For common folk they're all the same, evil savages. Let's remove all of them just because common folk doesn't know the difference, or just don't care to understand?
Re: "important things happen in the Material Plane": we can all agree that the vast majority of campaigns happen in a Material Plane, and the most important events of those campaigns are the actions of the PCs. So what I meant is "why do I use daemons to meddle in PC affairs, when I already have demons and devils for that?"
What you said about loths hating gods -- and by consequence mortals -- is interesting. But isn't that the most common motivation of devils (and sometimes demons)? For instance, arcanaloths keep pacts in their books. Isn't pact-making the devils' schtick? Why use an arcanaloth instead of, say, a malebranche? From a mortal's perspective, what makes them different?