Monstrous Organisation
The many monstrous humanoids found throughout Leng are generally considered to be uncivilised, disorganised masses. Even amongst those scholars who are wise enough to know of the terrifying monstrous kingdoms found in the north of Leng, there is a tendency to dismiss any smaller group as a rabble. This is a mistake that scholars can afford to make, but one that any general knows is deadly. Not all monstrous humanoids are created equal, and their organisation can vary considerably.
Gnolls
Gnolls are perhaps the species that conforms most the classical image of monstrous barbarism. They are savage marauders, with little purpose but to kill, steal and eat. They never set up permanent camps, although they may linger for a few days at the site of a particularly great slaughter.
A gnoll warband is on the move at all times - if you find one resting, it's going to be in a place they've just burned to the ground. They will likely use the ruins of whatever structures remain as shelter. They won't waste their time setting up a real camp. No tents, just carnage, and within a week they will move on to the next slaughter.
Goblinoids
Goblins, hobgoblins and bugbears are all commonly found together. Obviously, they can all appear individually in dens and lairs of their own, but when they mass for war they do build camps. A goblinoid war camp is very regimented - especially if hobgoblins are around. Even the brutal bugbears can provide a disciplining influence of cowardly and conniving goblins. A pure goblin army is likely to be extremely chaotic, though they attempt to ape the military discipline of the larger subraces.
Orcs also have a very regimented structure - though more savage in execution. Whereas a goblin army headed by hobgoblins will be strictly regimented with military discipline, an army partly or wholly composed of orcs is likely to have a more religious bent. Their hierarchy is based on the blessings of their gods, so warriors will sleep in one area, the chief in another, and priestesses and healers in their own quarter. Orcs often go out on raids to bring glory back to their stronghold, so there will tend to be a strong hierarchy of chieftains and established veterans. Though savage, orcs still make camps and keep a careful lookout for trespassers or vulnerbale passersby.
Whatever the subrace, goblinoid war camps resemble human military outposts. They will have ditches and latrines, a command center, tents for goblins, dens for bugbears, and so on. There will be organised roles, such as medics and a quartermaster to oversee provisions.
Kobolds
Kobolds don't have raiding parties, and they definitely don't make war camps. As a rule, they don't go to war. They are weak creatures that focus on surviving rather than raiding. They are uncomfortable in sunlight, and will likely retreat back to a cave system and fill the whole thing with traps and escape routes, rather than create a tent camp. That isn't to say their cave systems aren't well organized, just that it would be a very odd sight to see a tent filled with kobolds in the woods somewhere. They will want to hide away to a very well defensible position which they can fill to the brim with traps.
When kobolds do go raiding, it will usually be an opportunistic affair against someone close to their lair. They don't march or travel for more than a few hours to reach their prey, and they have little in the way of discipline. Mostly, they just boil out in massive numbers and hope to overwhelm their opponents. If there is a cleric with them, they might follow his guidance and form together enough to lay an ambush or set traps in the path of their quarry, but that's about as far as it goes.
Ogres
Ogres do tend to make camps, but they are usually found in "bands" rather than organised forces. As few as 2 or as many 12 ogres will set a fire and spread out furs to sleep on, but they don't stay in one place or build permanent war camps - nor do they usually mass or march in great numbers. Their camps are more akin to the campsite of an adventuring party or wandering brigands. When they do gather in large numbers, they will gather in towns and cities. A "civilisation" of ogres might have properly discipline armies, after an ogre fashion, but this is not a commonplace occurrence.