The 24-70 F/2.8 II and the 70-200 F/2.8 II are the only L glass I use on my 5D MK3 now.
I sold all my primes when I got the 24-70, it's that good
-1000... I own both II versions of the 24-70 and the 70-200. Great lenses but could never replace the primes, that's just a bad move selling them off 200 f/2 blows the doors off the 70-200, then there is the 85L, 50L, 35L, 24L, 135L... the list goes on and on... all of which offer something that zooms don't.
They are tools... zooms are great for general stuff but primes take over where zooms leave you... if you don't have them available another pro will take your buisness.
Well, I wouldn't know anything about a pro stealing business.
But I will always sacrifice some versatility for speed, and primes do that quite nicely.