Congratulations, you've just rediscovered the difference between Combat As Sport and Combat As War. In Sport, the encounter begins when initiative is rolled. In war, it begins with the recon you conducted two weeks earlier. Acquiring "cannon fodder allies" is the PCs' responsibility. Anyway, you're right, you would hate that kind of game.
Probably not. I just dislike a game where the DM fudges the most logical decisions/actions of the NPCs to allow an excessively lopsided NPC advantage become a disadvantage and protect the PCs.
I guess my understanding of the two was closer to:
Combat as Sport vs. Combat as War: a Key Difference in D&D Play Styles...
People who want Combat as Sport want fun fights between two (at least roughly) evenly matched sides. They hate “ganking” in which one side has such an enormous advantage (because of superior numbers, levels, strategic surprise, etc.) that the fight itself is a fait accompli. They value combat tactics that could be used to overcome the enemy and fair rules adhered to by both sides rather than looking for loopholes in the rules. Terrain and the specific situation should provide spice to the combat but never turn it into a turkey shoot. They tend to prefer arena combat in which there would be a pre-set fight with (roughly) equal sides and in which no greater strategic issues impinge on the fight or unbalance it.
The other side of the debate is the Combat as War side. They like Eve-style combat in which in a lot of fights, you know who was going to win before the fight even starts and a lot of the fun comes in from using strategy and logistics to ensure that the playing field is heavily unbalanced in your favor. The greatest coup for these players isn’t to win a fair fight but to make sure that the fight never happens (the classic example would be inserting a spy or turning a traitor within the enemy’s administration and crippling their infrastructure so they can’t field a fleet) or is a complete turkey shoot. The Combat as Sport side hates this sort of thing with a passion since the actual fights are often one-sided massacres or stand-offs that take hours.
Our fights are not always between two roughly evenly matched sides.
And the fight you described was not a one-sided massacre for the PCs based on their brilliant plans. It was a "I'll make it look like a tough fight, but in reality as the DM, I'm not going to really do that". It sounds like you might be playing a third style or a modified CaW.
And quite frankly, I think that the tables I've been at often have a little bit of both of the CaS and CaW styles. The 12 on 6 fight I mentioned earlier was the party knowing that there was a large enemy force nearby, so we wiped out a small group of the enemy in a side camp and set up an ambush (with traps and plans and such), waiting for when reinforcements would show up to investigate why the side camp wasn't sending back reports (we even had fake letters created so that if we had to abandon the side camp, the NPCs might be misled to our future intentions). The reinforcements, though, were really tough. It wasn't us winning because the DM thought we came up with a great plan and the DM did not hold our hands on it. The entire intent of our plan was to whittle down the large force and to trick them into sending out groups to look for us where we would not be. It was not a "just go in and fight a basically even set of foes once initiative is rolled situation".
One comment that I found amusing from that thread was:
I used to have what you'd call a "combat as war" style.
The problem was that eventually I started to recognize the man behind the curtain. I knew that I wasn't actually coming up with brilliant plans to defeat the monster, I was, at most, coming up with brilliant plans to defeat the DM. But that's like a four year old wrestling with his father- you only win if (when) he lets you win.