Duplicate-itis
Yeah I suffer from that also. I used to pick up a few duplicates of most of the common chips I bought, especially the illegals. Then about 2 years ago I realized how many duplicates I had. So I tried to stop getting duplicates. Well I am down to a few thousand duplicates now. Geeeeeez! I had just started getting rid of them when ebay raised their fees and required paypal. Just my luck! With prices you get today you can't afford to sell on ebay unless the chips are of a higher value.