Sneaked moose??

[Agrajag]

They don't actually enter the city, they just wander around the nature surrounding the villages of the province.
The reason they can sneak but say, wolves, can't, is because the wolves aren't smart enough to manage themselves, they all follow the wolfherd, and if all of them are around the wolfherd, you'll notice that huge herd of wolves. The moose riders have their riders to control them, and so they can split up and wander around independently.