By this point you may be asking, "Okay, but what does this have to do with the WSG?" Well, to answer that question, quite a bit. I feel that a lot of the animosity toward the book is not so much directed at it's content as it is at the misconception that it must be used. I believe many felt required to use it's contents due to some of Gygax's earlier statements covered above.
The fact is that many of us are now used to mixing and matching bits and pieces of systems that we like and discarding those that don't work for our groups or play styles. The OSR has made this a perfectly acceptable practice but back in the day there was a perception that you were either following the rules or you weren't. I would posit that higher adherence to the published books was the norm at the time. Therein lies the problem. No one could be rightly expected to follow and use every rule in this book. Doing so would be an exercise in tedium. However, I would argue that as a sourcebook and supplement the volume is excellent.
There are a lot of wonderful ideas, charts and systems in place for those who choose to delve into them. In fact for a book with a $15 dollar price point at the time (likely even cheaper now in most cases) this was/is an absolutely spectacular value for the amount of data and content it provides. $15 dollars at the time was basically equivilant to two modules by the way. Quite honestly if you are running outdoor adventures or a sandbox style campaign this book really is a no brainer.
If you have ever had qualms about picking the WSG up set them aside and try it out. Even if you can find nothing of value in the text of the book, which I believe is virtually impossible, the art alone is worth the $10 to $15 dollar investment. As a bonus most of these books tend to be in excellent condition due to the large amount produced at the time.