Beoric
8, 8, I forget what is for
I see this, not so much as a random encounter, as procedurally generated content generation (which I think is how it was originally meant to be used, when exploring wilderness that the DM had not keyed).As an example of the former, think of all of those AD&D monster entries that have "number appearing: 30-300." If 286 orcs show up, that's not supposed to be a mere "combat encounter" that's over in a few moments one way or the other. That's practically an invading army, and you might begin interacting with them long before you meet them, by seeing empty fields, burning villages, or refugees trudging hopelessly along the road. The metapurpose of these kinds of random encounters is to add INTEREST and DYNAMISM to the world, to give players things to react to and play off of. It could be 30-300 orcs; it could be a traveling circus run by P.J. Barman with strongmen and acrobats for hire; it could be a sphinx occupying a key trade route and demanding riddling opponents or tribute; it could be an ancient battlefield generating spontaneous undead war parties. At any rate, it's not something I necessarily need the players to resolve right now so much as I need them to know that it's there, now, as part of the context of whatever else they're doing during this adventure. And of course if they do start digging up the battlefield looking for the source of the unrest, they'll find something worth their time.
BTW, the Fiend Folio borks this, by nearly always giving dungeon encounter numbers, instead of wilderness encounter numbers; whereas the Monster Manual gives wilderness encounter numbers for anything that can be encountered in the wilderness. This is why the MM usually discusses the community structure associated with a set of numbers (like the number of leaders, or the fact that if more than two dragons are encountered, the third and fourth will be younger offspring).