My god... it's like you knew what the model was! Those thieves cheated someone by playing a model that was OBVIOUSLY what they said it was at the beginning of the game, possibly to test play it before actually buying the miniature.
Seriously. Guys. IT'S A GAME. Get over yourselves and let people play with whatever mans they want to. You're all mostly grown adults. Use some of that noggin and just ask or remember what things are.
Borderline alcoholic and happy about it.
Don't get your religion mixed with my Constitution. The mixture curdles.
I've been gaming for around 27ish years. In this time, I've played a variety of TT miniatures games, and have accrued an army or two for all of them. Not all of these games are still around or being played, but I still have the miniatures. Most of them have analogues to the "human" based forces of 40k. They were used in RT 40k games, a game which allowed a lot greater flexibility with models and minis (vehicles especially, since they didn't have many, but the rules allowed for so much more).
Why wouldn't I use them in 40k? Power armoured troops are power armoured troops, whether they are 7' tall genetically modified superfreaks or average joes in PA. Regular grunts are regular grunts. Tanks are tanks.
My SM army has models by Mantic (The Jotunn Hailstorm cannon makes a good Thunderfire cannon), my guard has models by Copplestone castings, Foundry and Grenadier, as well as pig iron, Scotia Grendel and Reaper (my rough riders are on VOID "akira" styled bikes, my tanks are by Pig Iron, my infantry is by a range of people).
I don't play in a GW store, so any such limitation for me is irrelevant. I pity those who have no option but to play in a GW store (we have 13 GW stores in my state - 11 of them are located in Sydney. The other two are the "regional" focus GW uses) there are so many better places to play.
There is (or rather, WAS) a "GW models only" purist in my club. Thankfully, he has now stopped gaming. He would only play GW games, and decried them as the be-all and end-all of gaming. That kind of narrow-mindedness is what kills a gaming hobby more than an openness to seeing what else is out there.
All this is now an irrelevancy for 40k now for me - I have discovered Tomorrow's War, a set of rules that allows me to use models by various makers, with the flexibility to fit them in like RT 40k had. Where humans in powered armour are humans in powered armour, tanks are tanks, and regular grunts are regular grunts.
I like the variety. Play with what you want. It is your money, it is just a game and if it is fun for both people then it doesn't matter. I taught my friends how to play Warmachine with GW paint pots!