God-Gale literally is not allowed to otherwise. It's basically the tragedy they build up for him in Origin, he still cares about his friends but he only has one channel left to interact with them - and most of them aren't interest in what he's selling. I don't think, human Gale was in any kind of favour asking position at the time. He does offer to make her a flying axe though, when she says she wants one. I think it's a bit sad we can't really craft one because the exchange is cute. ^^
But considering Karlach is pretty heartless in regards to him, the whole gang is heartless towards Astarion on the docks, the whole can of worms that is Halsin and the brothel ... there are some weird writing choices that make the characters seem crueler than they are supposed to be.
Well, Gale has some pretty ruthless commentary himself, like when you give up Shadowheart to the temple, he says something along the lines "our loss is our gain". I'd like to take him on an evil spin sometime, if only the evil route wasn't so lackluster.
