Research libraries need books for a very obvious reason: Authors before the 90s did not write their content to be easily indexed by a search engine. That's what the keyword card index was for! I agree that the internet is the best first step for researching, but as articles age, they will become harder and harder to find.

When I wrote research papers in college, I always located the hard copy of articles I found online. I would yank the whole year of publication off of the shelf and spend some time digging for buried treasure. Sometimes it was a waste, but other times it paid off!