In most cases, (aside from pharmaceuticals), the time that it takes to actually get a patent is so much longer then the time it takes to bring a product to market and technology advances so quickly that only overly broad patents are of any real value because they skim off the profits of others long after the the original implementation.

As for sharing the ideas, reverse engineering has advanced to such a point that once a product has been brought to market, competitors can figure it out in short order anyway. The only way to remain competitive is to continue coming up with new ideas that advance the state of the art.