So, I have been wanting to crunch some numbers for a while now, and decided it was time. Which expansion is the most expansive per tile (all other factors such as wood pieces or cardboard tokens ignored)? To do this, I used the official published prices of every salable Carcassonne expansion with tiles (no Phantom, no Spielbox or RGG promos) and gridded the whole thing out. I used the original German Euro prices rather than the US prices, though it would be interesting to see if there is a difference between the two. I was a bit surprised by the findings:

The cheapest per tile expansion is, naturally, the base game, where you get 72 tiles for a measly 0.24 Euro each. The cheapest expansion is Count, King & Consort where 34 tiles cost 0.32 Euro each.
On the upper end of things, the most expansive full expansion is The Catapult, which costs 1.00 Euro per tile, a bit much for a terrible expansion. Even more expansive, though, is the promo expansion The School, which costs 1.50 Euro per tile (and there's only two!), though I guess you get a large transparameeple in this.
Remember none of these numbers take into account wood pieces, cloth bags, extra cardboard components, or promo books. This just analyzes the expansions for the amount of tiles they contain, which is really the primary reason why people buy most of these, let's be honest here.
Check below for a comparison to US prices to find a few similarities and a few differences.
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