Good analogy. Cage free is expensive relative to floor for these reasons:
1. Disease control is far easier in cages where sanitation is excellent.
2. Movement around more may appear to be better but movement means energy consumption which translates to higher feed costs.
3. Cages keep most wild birds out, thus reducing diseases like avian influenza.
4. Cage based systems have automatic feeder and watering controls far more precise and protected from fecal matter whereas floor based systems cannot avoid feces in the feeders and watering troughs.
5. Eggs are cleaner and far less exposed to chicken manure /feces.
6. Egg collection is automatic in caged systems where the eggs are laid by the hens and it rolls down the slight incline to the belt which continuously moves the eggs to the processing area (candling, boxing, separation of whites /yolks.
7. Caged systems result in far fewer wasted eggs due to contamination and breakage.
9. Egg production requires stringent control of air temperature, air movement (fresh air), lighting (length of daylight impacts productivity), which are all easier to control to ensure correct amounts in caged systems.
10. Far less cannibalism in caged systems than on floor systems. (they eat each other).
11. Snakes, rats, mice, other vermin are far more difficult to control in floor systems than caged.
Above are just a few differences.
As to range systems, a nightmare from the disease control perspective.
Egg production is far less in range systems. Nutrient control is virtually impossible on range systems.