My pet peeve when downloading articles from journals is that it is a chain of needless HTTP redirects and elaborate cookies. If you are accessing the network from an approved IP address, is all that really necessary? Why can't it be a simple direct download? Answer: Because they've commercialized the process of reading publicly-funded research results. And with that comes the usual mindless hoop-jumping for even the simplest things.
Many investigators will just post a copy on their lab's website anyway. And that's the link that they will often give to students who need a copy of the paper. So the whole scheme of commercializing the publishing of noncommercial research just looks silly.
Don't question it, just follow along.