Eproms in common C64 carts?

[Goodwill Hunter]

Just found a bagful of C64 carts at a thrift (the best being Juice by Tronix) and was preparing most of them for auction. There were duplicates of 3 common carts in bad shape, so I decided to crack them open. Tooth Invaders revealed a standard PCB with 2 chips on it. Speed Bingo/Math and Jupiter Lander, however, both had PCBs with a single chip socket to the right with an Eprom socketed.

Any significance to this? I was under the impression that Eproms were for prototypes or other unusual applications. Why would they be in common production carts?

Rich

[NineInchSnails]

what is "eproms"?

[theaveng]

Erasable Programmable Read Only Memory. They are typically erased using ultraviolet light.