Oh boy... I remember some games having manuals that were hundreds of pages long...
These alone would probably cost about 10$ in production... and that's just the tip of the iceberg.
So yeah, the games were more expensive, but you got much more with them. Might want to compare the price of the games back then with the special editions today, and then you'll see the price didn't really drop all that much.
The Nintendo eShop rating Thread: http://gamrconnect.vgchartz.com/thread.php?id=237454
The Steam/GOG key gifting thread: https://gamrconnect.vgchartz.com/thread/242024/the-steamgog-key-gifting-thread/1/