All web traffic should be encrypted, regardless of purpose. This increases the work that nation-state level adversaries must do to effectively spy on the population. And it's cheap and easy to do these days.
Fair enough. I don't think this is a "shady" practice either. But I think it's an old, out-dated practice to charge extra money for a feature that should be on by default.
Why not ask the archive.org guys to publish it somewhere? The research already relies on their data and they seem to be pretty good at defusing shady legal requests.