What if I don’t want to burn the barge?

I’ve just got started with _Death on the Reik_ and, well, I’m going to make a few adjustments to make it less linear and so on. But one thing sticks out:

If I need to get the PCs to Middenheim, why don’t we just… give them a cargo to take there? Looking at the canonical maps, there’s a tributary of the Talabec that takes a boat most of the way there, with only a few miles overland.

Burning the barge just seems a little heavy-handed.