Randolf didn't want to offend the third Prince, not because he was afraid of him, but because he didn't want to go against the third Prince. Now, there were several princes fighting for the throne, and each of them had a chance to ascend to the throne. They didn't want to support one, and of course, they didn't want to offend that one either, so Randolf didn't want to interfere in the business in the sea.
Zhao Hai didn't tell him about the beer and liquor business. The liquor and beer business hadn't reached mass production yet, so Zhao Hai didn't want to take them out too early.
Things like beer and white wine were definitely the only industry on the continent. Zhao Hai was not prepared to cooperate with one person, so the third Prince and the kalci family would both do this business.