What's the deal with prime lenses

Hi,
I have used numerous Nikon AIS zooms and I can honestly day that they are as good optically as primes. The 25-50mm f4 AIS is as sharp as my 50mm f1.8 AIS @ f5.6- f16. The Nikon 75-150mm E f3.5 AIS is super sharp everywhere, as is the 50-150mm f3.5 AIS. The Tokina 100-300mm f4 was like a prime at all focal lengths. The Nikon 14-24mm is comparable to a prime lens.
If you need/want to shoot at 1.4, 1.8 or 2.8, or are looking for a smaller, more lightweight/less intrusive package, then a prime might be the best option, but I think we've reached a point where the top end zooms are every bit as good as the primes, optically speaking. Some may have barrel distortion issues, but there are numerous programs out there that can successfully correct this.
I do agree that the limitations inherit in using a prime can/will force a photographer to become more creative, or at the very least see the subject differently, but there are times when that same limitation will rob you of an opportunity.
Regards,
Mark