Do you have Sake Den at campaign start? Sake Den and market are merged into one building chain in TROM. First building is the merchant district. Then you can either build a Sake Den or a market. You should not be able to build both in the same province or two of them. Also you can only have one Sake Den and one market at the same time. Only after upgrading to the next higher building you can build another one. This pervents spamming of markets and also forces the AI to have more diverse province buildings.