As long as your going one-to-one, and not multiple like you suggested, I see it making no difference. A $100 male spider to a $600 female pied will provide the same as a $600 male pied to a $100 female spider.....
I personnal don't see this as a reason for not doing business with someone, if he thinks it helps make a bit more cash, and isn't harming the animals, why not.