Eh, most of the gods mentioned are evil and thus are supposed to be jerks. Most of the good and neutral gods like Selûne and Lathander do act pretty decently in the game.
The exceptions are Silvanus and Mystra, as stated. But Sylvanus is a very passive neutral deity, and is unlikely to get involved unless the balance or nature itself is threatened. Mystra, on the other hand, has a serious dilemma - Gale did something very stupid, and since he's almost inevitably going to blow up, he might as well do so somewhere that will have meaning and actually serve some purpose in removing a threat. It is fairly callous, but it does have some logic to it.