I posted something similar to what the OP said back when a18 came out (or was it a17)?
The Fun Pimps just want you to fight the horde. They don't want it to be a choice. Which is really weird because their game seems to be all about handling the situation in the way YOU want. Except the horde.
It's a huge failing on the part of this development team. Instead of letting players deal with the problem in the manner they decide (be it having some kind of fortress, digging a bunker, making a kill-tower, outrunning the horde or whatever), they continue to try to railroad the player to this