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Anyway, everyone is using it to make money, but your still not making a ton of money from it, once people start getting there own towns, businesses, etc, people will stop using it. Fishing was one of the best jobs in the old eco, but it was still never better than owning a legit business.
EDIT: There definitely needs to be some sort of level cap, or maybe slowing down the bonuses per fish once your in higher levels, but nerfing fisher for everyone will only hurt newer people, not the people who make 500 meebs per fish.