I don't think you're taking all the cost factors into consideration, for one you're assuming that the audience would grow when it probably wouldn't, rather the current fan base would split in some ratio of censored:non-censored, which would make them lose money. And why would anyone waste pages reprinting a series when you could make more money off of a new one. Plus what would be the drive for people to buy the tankubans if they did that. It's genius marketing damnit, genius.