I've gotten one of the BurgerTime cabinets. It is a "Micro Arcade" from a company named "My Arcade" I've torn it down, and looking at the innards. It looks like the screen's driver, audio and the driver for the controls may all be buried under the bulk of the black goop they poor over the main chips. I've never removed that before, but I'd be willing to give it a try. Getting this thing apart required carefully removing almost every single sticker. Luckily, the stickers are very thick and made very well. I was able to pull them off with almost no visible damage to the stickers themselves.
This is the closest image I could get so far, showing what I'm currently assuming is an audio chip. Also, the ribbon on the right is to the screen, it is soldered to the driver board instead of using a quick connect clip.
*EDIT* The chip is a WINDBOND 25Q32BVSIG.
I'm seeing it labeled as a "Graphic Chip" so far. It is a Flash Memory. The datasheet is at
http://html.alldatasheet.com/html-pdf/443794/WINBOND/W25Q32BVSSIG/299/1/W25Q32BVSSIG.htmlI'll keep researching, and need to figure out how to get this black silicone goop off to see if it's a all in one chip, or if I can solder things to the driver. Right now, I'm not thinking I'll be able to reuse the screen with a pi.