Ahh, good, I get to edit this before anyone answers. This always happens to me. I get into these kinds of discussions and get sidetracked by pedantic minutia. It's not important that there are orcs in G1. Scaling does occur in 1st Edition D&D and I can prove it.
Look at the cover of almost every module ever produced. Right next to or underneath the title you will see a line that says "For Character Levels X to Y" or something very similar. That's scaling.
If there was no scaling then I could take my 1st level character into Queen of the Demonweb Pits and expect to succeed. I could take my 15th level character into Cult of the Reptile God and expect to be challenged. Neither of those statements are true. Why not? Because adventures are scaled to challenge the level of the PC's that they are designed for.
Looking at something like Star Frontiers, which doesn't particularly scale, you see that the challenges in all 4 Volturnus modules are all on the same level. Or pretty close. A beginning Star Frontiers character is not particularly weaker than an experienced one. HP's stay the same. You might hit better, but, other than that, there isn't much difference.
I haven't played enough Vampire, but, from what I saw, I would say that V:TM doesn't scale as well. A just made character isn't all that different from a character that's been played for a while. Teenage Mutant Ninja Turtles also didn't particularly scale. A fresh PC is nearly identical to one that's gone through several adventures.
That is simply not true in any version of D&D. (Whoops, before the pedants swoop in, let me say that I have no experience with OD&D and should qualify that last statement.) A 1st level character and a 15th level character are vastly far apart in every measurable way. The PC's grow in power as they gain levels. That's the point of a leveled system. In any leveled system, there has to be the concept of scaling adventures, even if it isn't expressly written.
I'm a bad DM in 1e if I randomly bomb my 2nd level PC's with an Ancient Huge Green Dragon and wipe them all out. Why? Because the threat isn't scaled to their level. While the random wilderness charts may not be scaled,
in play there is the expectation that the DM will provide challenges that are neither too easy nor instant death sentences. Or, at least if he does so, there will be an out clause somewhere along the line.
It's like the idea of PC wealth. While it's expressly written in 3e, the idea of wealth by level certainly existed in 1e as well. The whole line of "Monty Haul" campaign advice is based around that concept. Sure, wealth by level isn't called out, but that's because the classes don't balance at the same level. A 7th level fighter and a 7th level thief are not expected to be at the same power levels.
But, there is still the idea that certain levels of wealth should be attained at certain levels. No one bats an eye at a 5th level fighter with a +1 longsword. That's pretty standard in most campaigns. However, a 5th level fighter with a +3 Vorpal Sword is a sign of a bad campaign. It's Monty Haul. Why? Because it's too powerful for that level of character. Thus, wealth by level is a concept in the game.
3e certainly didn't invent any of these concepts. 3e only specifically called them out as a baseline.