Here's a great blog post from american journalist Andrea James about why you should hire a photojournalist. My favourite is number 3...
"3. Consider your moment captured — How much would you pay to make sure that THE moment of your event is captured forever? This is what photojournalists are trained to do every day. At my own wedding, I knew that I didn’t have to worry about making sure our photographer (and friend) was capturing crucial moments. He was everywhere. When I saw the photos, I was delighted and saw new aspects of my own wedding that I had missed."
Read the rest here : Five Reasons You Should Hire a Photojournalist