@KazuyaKan one reason is color is EXPENSIVE. Coming from a guy who trained in Graphic Arts, and only just dabbled in consumer printing, more than 3-5 colors will cost a pretty penny, upwards of 60% of the entire cost to produce a single page will just be color, up to ~80ish% if its way more than 5. There's that cost, and scanlators go about how they work differently. Some literally import issues physically, others just use the raws found online, and one costs more money than the other.