Part of the reason that subscriptions and micropayments haven't caught on is that people put up with ads. If ads stop working as a business model, I doubt we'll be looking at a bleak future of watching Love Boat reruns and rereading old Family Circle articles. We will find some other way of funding good content.
Indeed, when I look at the way the quality of television has improved over the last couple of decades, I think it's a reasonable argument that blocking ads would be the moral imperative. As anybody who has worked in ad-supported industries knows, consumers aren't the customers, they're the product. Rather than being served, viewers and readers are being served up to advertisers. The system has a conflict of interest at the heart of it. It's reasonable to refuse to support corrupt systems.