So Im currently playing pathfinder for the first time, playing a sorcerer, and my GM says I must learn all new spells through scrolls, but this seems pretty BS as Im limited to the luck of the draw or whatever I find in shops which seems to ruin any chance I have of building up any money what so ever for things that cost any more than a few thousand. His argument is that it makes it so I just genesis spell knowledge every level and that I can just learn the most powerful or most useful spells, also it just makes it so I as a player do not participate in spell knowledge. This nerfs the sorcerer pretty heavily and I cant seem to convince him of that.

edit: I talked to him, using some advice you guys so helpfully offered, and he said he would reconsider his stance on the whole thing, as there is also a Bloodrager in my group and they "genesis" new spells the same way as Sorcerers.