Good question!
This project is part of a global domination scheme! Haha no!
Actually, this project is part of a larger group of projects which I am working on for the TG-16. I needed to test whether or not adding a propagational delay on the databus had adverse affect - old ROM chips are pretty slow and I was worried that more delay might be bad. These chips cost pennies, are fun to solder, and once I created the PCB I didn't bother to make a new one without the ICs because I am always short on time!
Also, to prove a simple point that I can make a product with 2 PCBs, a custom connector, take the time to solder it by hand, include 3 ICs, and not charge an arm and a leg...