If the galleries the uploader was replacing had visible compression artifacts then I'd understand his behavior, but all he's doing is blimping the filesize and swamping the network with duplicate crap, at BEST replacing efficient galleries with ones that have larger filesize, but no visible improvement at all.
Short answer? Getting NEW games and ripping them before someone else does would be WORK and could cost him MONEY. Since he doesn't want to spend either, he takes the cheap route of grabbing torrents of things already on this site and lazily replacing pictures that have good compression/loss balances with 100% non-lossy, which doesn't actually give an improvement that a person without a microscope can see, especially with older, lower-res games.
Base +6, ywmls +6, Irregular Hunter X +6, GT1 -8, Tremalkinger +7
@Ryann In terms of visual quality, it might be true that most people will not notice the difference between lossy and lossless images. But if you want to archive something in its purest form without any quality loss, i.e. lossless, then lossless image format is a way to go.
Having said that though, we don't know the actual image format that was used by the studio when developing the game. If they were using PNG, then we have exact lossless quality rip, which is good. However, if they were actually using JPG, then we just simply wasting our harddisk space. Compressing JPG to PNG files are pointless. ;-)