"Limo."

I suspect Doom totally has a limo, he just doesn't want to give them a ride... I know Kang guested in the recent Doctor Doom series, but I haven't read all of that to know why. Hopefully, my explanation makes sense, since I think I've figured Kang's long game out, and why he's never time-murdered the Avengers or anything. He's using them the way a gardener would use shears, to trim the topiary of time into the shape he wants it. There was a hint of this in Busiek's run, where Kang mentions multiple horrible possible outcomes for earth, like the Days of Futures Past timeline. We'll probably get more into this.