Well, none in this city! I've never heard of a single cockroach here!
I've seen plenty of cockroaches in Eugene, believe me. Of course, out here, we just call them "bums."
*rimshot*
Anyway, the main problem with buying games in the Northwest is mold. Jesus, there's so much water & mold damage to the used games out here! Games that come in a DVD case usually have covers that are wrinkled from the moisture, and sometimes stuck, in spots, to the outside plastic sleeve. Just gross. I've bought cartridges that have mold on the contacts, and labels that are covered in tiny, white, moldy specks. Hell, even the used CD-based games I buy have moldy patches on the playing surface.
Of course, Eugene being a college town, a lot of the used videogames in the area were likely ditched by the kids moving out, then later found in a dumpster / curbside "free box" by someone else. Days could go by before someone claimed someone else's unwanted games, and in that time, they've been rained on & soaked. You can usually tell "dumpster games" when you see them, especially if the seller has a soggy cardboard box full of cartridges, and wants his trade-in value in cash. I've seen that more times than I care to admit...