With an income of 1,500 pounds per year, the Irishman is seriously wealthy, and he is willing to give Moll a dowry, instead of the other way around. The Irishman seems too good to be true, which suggests that he probably is. His fortune is in Ireland, and he can easily lure Moll to Ireland on the pretense of money, and by the time she discovers the truth, she’d be trapped there.