1. You can carry huge tanks (instead of several smaller ones), including ones that were NOT intended for that, meaning you can surprise an enemy by deploying some weird weapon where he doesn't expect.
2. You can carry trains, and then use those to carry the rest.
3. You can carry other airplanes, for example if you end in a war of attrition and need to crank out planes as fast as possible, it might be an interesting idea to make them even far from the front, and ferry the plane parts to the front (then assemble there, and use them).
4. And most interestingly, it can carry gigantic parts of whatever you need, warship propellers, munition factory machinery, and so on...
It is tempting to think it would be interesting to use as bomber or paratrooper plane, deploying a huge amount of bombs in the same place and levelling it completely... but this would be a terrible idea, a plane that big is probably a huge target, people would attempt to shoot at it even with small arms, and it is not impossible to get lucky with them (happened at least once in Iraq War for example, when a random farmer downed a US helicopter right on the start of the war with his hunting rifle... the chance of it working was tiny, the rifle didn't even had the range to ever reach the helicopter, but somehow, it did...)