One of the oldest and most hotly debated topics in photography is the issue of whether one should use prime or zoom lenses. If you are new to photography and wondering which category is right for your work, check out this great video on the topic.
Coming to you from David Manning, this helpful video discusses the differences between and respective pros and cons of prime and zoom lenses. Traditionally, prime lenses are sharper than zooms, but in the past five years or so, we have seen tremendous steps forward in image quality among zooms, though primes generally still hold the edge. Even so, primes still hold the advantage of wider apertures, generally smaller and lighter designs, and often lower prices. Of course, the advantage of zoom lenses is their versatility in focal lengths, which can be more than a convenience and actually a necessity in some cases where you can't physically move or need to change focal lengths more quickly than you can change lenses. Personally, I prefer a prime lens when I know the exact shot I would like to get, but I will normally opt for a zoom in situations that require me to be more fluid or in which I am not sure how I want to shoot. Check out the video above for the full rundown from Manning.
A good summery of the decision making process when buying lenses. The only two zoom lenses I own are the 16-35/4L and the 70-200/2.8LIS and they are for very specific types of jobs.
As a wedding photographer I definitely enjoy the range and flexibility a zoom lens has to offer. When shooting a wedding the idea is to be everywhere all at the same time while also not being in the way and a zoom lens offers that all in one package. Then, for those more artistic shots, I use a prime lens. I haven't had a zoom that can blur a background in close proximity like a prime lens can.
I actually shot one yesterday with just primes. I made a comment that I don't have a good 50mm (only the cheap Canon 50 1.8 which I do adore, but does show its price sometimes). The groom, who is also into photography and owns an arguably better kit than me, asked why I don't buy the Tamron or Sigma 24-70. Simple answer: I prefer primes.
In the prime vs zoom debate, it all comes down to preference. I own a DSLR 24-70 and a 70-200 f/4, but I only use them when I have no option of movement (ex: roped up trying to shoot rock climbing). But for me, I'm at my best when I'm using the focal length limitations of a prime.
To your point, though, if I did more weddings (I only do a couple a year), I'd probably upgrade my 70-200 to a 2.8 for those cases where you are constrained.
It's a bit of a weird lens, but I recently bought the Tamron SP 24-70 f/2.8 G2 for my Canon 5D Mark IV and it's super sharp for a zoom. I have used both versions of Canons 24-105 f/4 L and I already like how this lens looks compared to those two. That being said, most of the weddings I have photographednwere done so with prime lenses. My wife and I are a team and each shoot with two bodies during the ceremony and until the reception. I shoot with a 50 and a 135 and she shoots with a 35 and 85, all Sigma Art glass.
Sometimes we will switch it up, it just depends, but those are our four main lenses. We love our prime lenses. My wife has always been skeptical of zooms but, so far, is enjoying the Tamron I mentioned earlier even though it zooms in the opposite direction of Canon zooms which can take some getting used to. We shoot video sometimes so I'm not trying to have more zoom lenses than prime lenses because zoom lenses are useless on a gimbal.
I have the G1 Tamron 24-70 and I've loved owning it. It's been a great tool, but has kinda been collecting dust lately since I'm doing mostly prime work on a mirrorless camera now. The weight of the lens + adapter + smaller size Sony body just doesn't make it as fun to use anymore...