Roll film and sheet film need to be coated onto different base materials. The cost of polyester has gone
up; then they've got to amortize the very specialized chemicals and dyes needed for color film in the face of declining volume, general inflation, etc - all these things add up. Then in the past I suspect that constant price wars between Fuji and Kodak for head-to-head items moderated things, to the effect that maybe this was a partially subsidized product category. But today Fuji has basically ceded color neg film to Kodak, and Kodak has respectively ceded the chrome market to Fuji, which means they can relistically factor profit margin higher. I don't really care. To me, one good shot on 8x10 film
is more useful than 500 with a small camera.