[MaxBarraclough]

The existence of a means of recourse doesn't undermine the point that they don't want eBay to have that power over their finances in the first place. Would you want your landlord to have unrestricted access (but for the law) to your finances? How about your neighbour?

By means of analogy: the utility of Android's fine-grain app permissions system is not rendered obsolete by data-protection laws.

It's especially galling as eBay could, presumably, just offer to wire the money over after enough time had passed that the buyer can't complain that the item didn't arrive as described. (This would cut out PayPal and card-transaction fees, which is presumably the whole point.) They choose not to offer this.