I remember that Sal Glesser told the story of how the Spyderco 'bug' got it's shape. When Spyderco knives first hit the market in '80's, they were, as Mr. Glesser put it, somewhat austere and 'sterile' in appearance. The Worker, Police, and Hunter models were only offered with Stainless scales and most had the 'then' revolutionary Spyderedge, which added to the cold and possibly aggressive image that the knives might have given off. As such, the decision was made that the Bug Logo ought to have a friendly and perhaps almost humorous/good-natured look to it, rather than making it look like a genuine spider, whose menacing and fearful nature might evoke even more negative vibes.
That said, we can see that the Logo that we have all come to love has rounded corners and a pudgy body, which would evince a more inviting and 'cute' appearance. Certainly a lean, sleek, pointy-ridden black widow spider would invoke a negative feeling in just about anyone (humans seem to have developed the tendency to respond adversely to venomous creatures like spiders, snakes, bright colored frogs, ect. If all of our ancestors went about picking up and hugging every spider, snake, and crawly thing they came across, humanity would be in for some trouble.)
The Spyder emblem, therefore, is cute rather than menacing.
I do hope I got the story right, or at least captured the spirit of the history of the emblem.