While the caves are non-Euclidean and infinite, any given path once traversed, is stable for 1d6 days, with modifiers based on the number of people traveling said path, and any markings they leave.
This means that if something nasty crawls out of a monster nest deep in the caves, there’s a good chance that its friends can follow. Conversely, an adventuring party can delve the deeps, follow the spore trails, and clear out the danger before more makes its way to the surface.
This stability, coupled with the fact that any cave diver is likely to return to their home canyon (if they survive the depths) means that a secondary form of adventure is available. Trailblazing new trade routes.
The normal method is to simply enter a cave, take the first turn available, and then make your way back to the surface, then use the sun and stars to see how where you are North to South. Then repeat until you have a useful trade route.
Most useful trade routes have 3d6 stops above ground. Finding a faster, more direct route, can lead to riches.
As a thought for clarifying things. The shifting caves are via earthquakes, cave ins, and tunnels that collapse into others.
This is much less likely to happen to caravan routes, mostly for narrative reasons.
Infinite ever shifting caves are incredibly useful to the story, being constantly lost is not. Not unless that is the story, and it should be the players who decide that.
If only through a botched roll.