There are lenses that I love that happen to be primes. The first two that spring to mind are the TS-E 24 II and the 400 f/2.8, but there're plenty others. The 180 macro, for example, is awesome for passport-style head shots, in addition to everything else it's awesome at.
There are, of course, situations where a prime would be a royal pain in the ass. I'm not a wedding photographer by any stretch of the imagination, but I did just play "Uncle Bob" at my niece's wedding, and I can't imagine using anything other than the 24-105 for the reception. (I'd definitely want primes for the ceremony and portraits, though.) Well...granted, I can imagine having enough experience at shooting wedding receptions to know how to do it well with primes, but even then I strongly suspect I'd still prefer a zoom.
Horses for courses and all that....