Yea, so I'm a wedding photographer and obviously I'm going to argue that you need me! However, let's be a bit more unbiased - here's 3 logical and factual reasons why you need me (or someone like me!) 1) For the rest of your life the only tangible thing you have from your wedding is photographs. Ok, maybe you keep your wedding dress but there's nothing to remind you of the whole day like a couple of hundred photos! Many couples will also have a wedding album which has been, and always will be the very best way to look back in years to come at your wedding.
2) It's HARD to do! Wedding photography is the pinnacle of the many forms of photography. It requires the photographer to be an event photographer, a portrait photographer, a product photographer, sometimes even a sports photographer. On top of all this a professional wedding photographer will also be an organiser - group and family shots don't happen on their own - they need to be created in the right location, with the right lighting and using the right camera equipment. Many great wedding shots of the couple that look completely natural are actually staged and created by the photographer - that skill and ability is what you pay for.
3) Photographic GEAR!
Ok, modern cameras and even phones give what look like great photos. Heck, I can remember a wedding where a guest took a shot that I was taking on his phone and we compared photos - his photo on his iPhone looked fantastic - mine on the back screen of my camera looked quite ordinary. However...
An image on a phone or consumer camera doesn't get any better - images from a professional camera allow a fantastic amount of editing and improving to give photos that will blow an iPhone into the dirt. Professional cameras start at about £2000 without any lenses. My gear here (£6k plus) allows me to get photos in almost total darkness, get shots where you can zoom in to see individual eyelashes at 10m and allow me to never miss that really important moment.
Finally there's the responsibility. A lifetimes photographic memories entrusted to a friend with a camera? Or some guests and their phones? Ok they'll get "some" photos and if your wedding day is only worthy of "some" photos then who am I to argue - but if you value this most special day there's no alternative to a professional wedding photographer
To get to the level of being able to confidently capture all the moments during your wedding day and create beautiful images that you'll love forever has taken many years. Honestly my first 10 weddings I look back at an cringe - but even these cringe-worthy photos are probably better than most non-professionals would get. Whatever you decide I wish you a great wedding day!