LOL. Every application uses a browser engine for text display these days. It’s not exactly unique to Adobe. Most coloured text components in OSX are rendered using good portion of the WebKit display engine, too.
Every program attempts to expand until it can read mail
Every program attempts to expand until it contains a web browser.
I think this is the opposite of something to gripe about. If I were an engineering manager at Adobe, I’d look at this as something for which memory usage is not critical to minimize: it’s a desktop app (so, demand paged), and not one that anyone keeps active for more than a few minutes. I have limited development resources, so I’d rather put them toward work on the product itself, not its installer, as long as the installer works well (including not feeling bad) for my customers. There’s an extremely-broadly-used rendering component we can use that works well and my designers already know how to use it? I’m sold.
(Obviously it should be set to reject drops!)