He said that he's tried and failed to make travel interesting for them. To me that implies that he put interesting things in their path and they didn't care.
It's not entirely that didn't care, but they only care about the explicitly interesting things. And I really can only come up with so many of those. Like if I say:
The road has become less of a road and more of a bumpy old ox cart for several miles now as you wind your way through the hilly grasslands beyond the Westwood. Most of this area is still unexplored, after the Dragonwars, when the forces of the Forestmaster, the ancient Green Dragon of the South faced off against men and Fey. The occasional subsistence farmer or small village is all you can expect from here on out, as there are many strange creatures in this region.
(Players start looking antsy)
As you round the bend, you see, on the top of a hill, a dolmen- a circle of ancient standing stones. The true purposes of such monuments is unclear, but Druids often claim them, saying that they tap into powerful energies that flow through the earth, water, and sky, called lee or ley lines.
(Player perks up): Oh yeah? I climb up to get a closer look.
As you crest the hill, you see there are many bones, mostly animal, but some human, strewn about the area. The central, or "altar" stone of the dolmen is cracked, as if hit by immense force. You are struck by a sense of evil...
(Players poke around, skeletons animate, fight occurs.)
(Player): Well that was weird. I wonder what the deal was.
(Other players): No treasure, what a waste of time.
(Me): Perhaps you should ask the locals, or a scholar in the next major city you encounter.
(Players): Eh. Ok, we keep traveling.
A month later, they're talking to an NPC and he describes some ancient ruins he's been looking into, as well as legends of a "Dead Man's Hill" a monument site somewhere.
(Players): .....
(Me): Really? You don't remember anything like this?"
(Player): "Oh yeah, we did fight some skeletons. Yeah Mr. NPC guy, we saw it, it's off this way. Oh go back? Well, we're kind of in the middle of this thing, and it's a long way. Unless you could teleport us there?"