I don't know much about armor modeling, but I've seen the same sort of thing in other phases of the hobby. I have several biases, one of which is the fact that I spent several years working in a hobby shop.
I agree that this is a great time to be a scale modeler; the range of high-quality kits, aftermarket parts, etc. has never been greater. On the other hand, we're currently witnessing a phenomenon that, I think, we all agree is pretty sad: the death, or near-death, of the local hobby shop.
There are many reasons why the local hobby shop is becoming extinct. One of them (not the most important, I admit) is the fact that it's physically and financially impossible for one local shop to stock all the wonderful things that the manufacturers are producing. It seems to me that the approach taken by Dragon with its "3-in-one" kits, or perhaps a variation on that theme, would be of big benefit to the hobby shops.
An example with which I'm more familiar: the 1/72 Spitfire kits from Hasegawa. The Spitfire Mk. VIII kit was released first, as I recall. A few months later came the Spitfire IXc. The latter kit contains every single part that's in the Mk. VIII kit; it's just as easy to build a Mk. VIII from either of them. The only differences between the two kits are in the instructions and on the decal sheet. The difference between the decals amounts to less than one square inch of paper. But if a customer walks into the hobby shop wanting a Spitfire VIII, and the shop only has the IX on the shelf, the shop loses a sale.
The same thing goes for the Hasegawa 1/48 Mitsubishi Zero line. The Type 11 and Type 21 kits contain absolutely identical parts. (Each kit includes two canopies, a tailwheel, a blanking-off plate to cover the tailwheel well on a land-based aircraft, and instructions to fill the grooves representing the trim tabs on the ailerons.) The only actual differences are a few different colors for the fuselage stripes on the decal sheet. But if a customer watches the movie "Pearl Harbor" on DVD, strolls into the hobby shop, asks for a "Pearl Harbor-type Zero," and finds only the Type 11 on the shelf, the store loses a sale. The customer then goes home and either (a) decides scale modeling isn't worth investigating after all, or (b) fires up his computer and orders a Type 21 Zero from a mail-order house. In either case, the chances of his ever setting foot in the hobby shop again are slim.
Hasegawa seems especially fond of flooding the market with duplicate (or near-duplicate) kits with different markings in different boxes, but other companies do similar things all the time.
What I'd like to see is a box labeled: "A6M Zero. Can be built as any of six variants." Or "Sherman Tank. Can be built as any of six variants, with either HVSS or VVSS suspension, and with either 75 mm or 76 mm gun." Or "Iowa-class battleship. Can be built as either Iowa, New Jersey, Wisconsin, or Missouri, in WWII, Korea, Vietnam, or Desert Storm configuration." Sure, everybody buying such a kit would end up with some leftover parts. But styrene is cheap; the actual plastic in a kit box accounts for only a small fraction of the price. (Remember: more than half the money the consumer pays for the kit goes to markup for the retailer, the wholesaler, and the manufacturer. What's left has to cover the expense of designing the kit, making the molds, designing and printing the instructions, designing and producing the box, advertising, etc., etc.) Contrary to what some manufacturers would like us to believe, the addition of forty or fifty small parts to the box contents doesn't increase the actual cost of the product by more than a few cents. Many modern kits contain lots of parts that the builder is instructed to discard.
I join everybody else in drooling over the huge variety of merchandise available to scale modelers these days. But let's give a little thought to, and have a little sympathy for, the people who make their livings by selling the stuff.