For better or for worse, airlines are not in "the regular business world." Fare rules can be incredibly complicated and confusing, with many different fares applicable for the same routes, etc. If you think having the outbound and return priced differently is "complicated," you should wait until you try doing something really wacky like stopovers, open-jaws, multi-city trips, open-ended tickets, refundable fares... and so on.

The pricing for each leg is visible in the "Fare Details" section of the e-receipt... it's hard to read, but it's there. You're right, it would be great if it were more transparent, the way it is on the LCCs... but the airlines have no incentive to make it easier for us to read the receipts.

Nevertheless, even if it were easy to read the receipts, you could still easily (and likely) have different pricing on the outbound and the return. Even the LCCs who itemize the fares on each segment often have different prices for O&R.