Of course they can, but they won't. This is their business model. We subscribers are their free labor pool. Ancestry.com collects our personal work and they resell it, really without our permission (although if you look real hard it is probaby in very tiny fine print buried somewhere.)
In addition, the company owning Ancestry.com is building quite an internet monopoly, gobbling up all the genealogy sites they can so that everything points you back to their site. Ca-ching!
They also make it very hard to download batches of document images, which I believe is intentional. Who is going to do all that work? Some people will but not that many. And those willing: it will take them a long time to download everything. Meanwhile Ancestry collects the monthly subscription fees. Ca-ching! Of course they can create an application to download document images in bulk. It would cannabalize their cash cow, though. Why would they?
Of course they can make nicer charts available and allow a better printing application right from the website. Wouldn't be profit-friendly, though. People wouldn't buy Family Tree Maker if they did that. Then where would they be? Of course they can make My Canvas more flexible -- but then people would buy fewer pages.
When will FTC get on their case? Because it isn't right.
On the other hand, there is a very nice business opportunity here for anyone who is even remotely more cusumer-friendly than the people running this show. This is really a gangland style of business. You buy because it is the only game in town, not because you like them. Leaves Ancestry.com pretty vulnerable if you ask me.