In practice, no, I'm not going to let you frighten Orcus into giving up and begging for his (un)life because one person made a high roll and now my climactic fight is scuttled.
Neither will I, but that's besides the point. I think the rules are simple, clean, and useful, here: NPCs can be willing, unwilling, or hesitant, as determined by the DM. The first two won't necessitate any roll. A willing NPC will accept, an unwilling one will refuse. So we're left with the hesitant.
Orcus won't be, surely. But these marauders who thought they were going for an easy prey (how they were mistaken!), after a round or two? I don't see a reason why they couldn't be. The rules give us the tools for it, at least.
All of which is just to point out that the game isn't set up to let people make good use of the Intimidate skill. Even if the rules explicitly tell you that you can intimidate creatures into surrendering, if it's just not going to be fun, it's not going to happen in practice. Gameplay routes around rules that don't serve it (usually).
But it
could be
more fun. Obviously, if everybody is here around the table for their 6-8 encounters-a-day dungeonny adventure and everybody's fine with combat taking most of their playing time, maybe you won't see frequent uses of Intimidate, because nobody at this table would find this fun.
But now picture a table where combat is supposed to be one or two twenty minutes interruption in a two-hour long roleplay session. Maybe everybody would be pleased if that band of marauders don't overstay their welcome?
In my games, lot of combats end before a side is at 0 hp. The losing side will surrender or try to parley most of the time. I prefer it like that, my players prefer it like that, it allows us to cram more actiony scenes in our cramped sessions, everybody wins.
This game is design to entertain
a lot of people, among them people with many differences in taste and ways of play. The skill system being fast and loose, simple and DM-oriented mean that they won't be used the same among all these different tables. And that's perfectly fine.