The merchant is surprised at Skellig's addition of wealth and well wishes. "May you and your wife have many fine children, good Sir." It's a traditional well wish in his culture, but one that Skellig might find a bit odd.

It is indeed tea, and the woman operating the bread cart is arguing with the woman who operates the tea stall over the merits of various spices and proportions. (There's no heat, no anger to the argument. This is, apparently, just how they are.)