In my dark moments I sometimes think that a lot of younger SF readers don't care much about the history of the field and that they don't want to read anything that wasn't published within the last five years. In my even darker moments, I think it doesn't matter. When I read the stories from any book in this series, I think what a great past SF has and what fine storytellers the field produced, and I'd like to require everybody to read every story in every volume. Fat chance. At any rate, I'm glad I have them all and can open one up and read a great story anytime I feel like it.
Some of the books in the series can be found on the 'Net for very little (the higher-numbered volumes are usually a bit more). Check 'em out.