There isn't enough difference in the heat content of regular and 'super' gasoline to make any noticable difference in the energy output from your engine. However, the super allows you to use an engine with a higher compression ratio without the engine experiencing highly destruction 'detonation' (i.e., the gas/air mixture igniting before it's supposed to). Also elated to the detonation  problem is the fact that the higher octane gasoline will allow your engine to operate with a more advanced ignition timing without experiencing detonation. In summary, the higher octane gasoline allows for a higher performance engine to operate safely in a higher state of tune that would be possible with the regular.  Again, thel relative heat content of regular vs super has virtually nothing to do with it.

I'm not sure if the higher octane gas requires more crude input or not, but I do know that it is a bit more difficult to make, which might be the reason for the slightly higher price.

From a refining standpoint, making high octane gasoline does indeed require more processing steps.  Since tetra ethyl lead was phased out some 30 years ago, various high octane blending components have come in and out of favor.  Currently, the blendstock of choice is "alkylate."  It is produced by reacting isobutane with C4 olefins using a corrosive liquid acid.  It's the type of safety-health-environmental concerning process that brings a lot of regulatory hassles and as a result there hasn't been much capacity addition.  And of course the demand-capacity inbalance is making alkylate even more expensive.

Higher octane gasoline operates at higher compression ratios without damaging the engine, so the peak temperature is higher, which is thermodynamically more efficient, so you get more miles per gallon if your engine will let you operate at the higher compression, which it won't because the nitrogen oxides produced also go up with peak temperature and that causes smog, which your engine is not supposed to do and why your chip set won't allow you to operate at higher compression.
You can buy chip sets for your car which will bypass the controls on your engine and allow you to operate at higher compression ratios, increase your pollution, and possibly wear out your engine faster as well. You won't pass smog while using those chip sets. You will win street races, though.