Varies a good bit for me, but almost always on trails (or forest service roads, or some sort of pathway).

I agree with Grumpy Gord's comment:
"I think that to a large extent it depends on where we learned about backpacking."
And/or perhaps just where you live now and what's in reasonable driving range for most trips. For me that's the Pacific NW.

But I also agree with the idea that what we're used to drives us very much --- consciously perhaps but also subconsciously --- in how we think about backpacking, our sense of what's "right and normal". I've never hiked in true desert, but have now done a fair bit of "close to it" hiking, places people refer to as deserts (CA, NM, WY, AZ). Quite different, lessons to be learned, but also some assumptions and biases to un-learn.