A hostile NPC doesn't need to because they tend to have home team advantage & can make use of a locked & barricaded doors/secret door/relocation trinket/trap/etc & the result is more interesting than "they cast tiny hut, it's opaque & you don't know what's going on.... nobody has dispel magic handy?... awww...."
The scenario is that the NPCs are invading someplace the PCs are guarding.
How would your PCs counter the NPC's tiny hut? If you don't have an answer that's fine. Ask your group when you get a chance.