Sure! But there are a few important caveats to recognize. First, guests should refrain from (or be exceedingly careful) taking pictures during the ceremony. The ceremony, more than any other portion of the wedding day, presents numerous time-critical instances when I have to be in a particular spot to get the shot for you, and it's very easy for a guest to obstruct this line of sight by trying to get their own shot while perhaps not even realizing the problem it is causing (leaning out or sticking an iPhone out into the aisle during the processional or the kiss, for example). For this reason, consider having an unplugged wedding, at least for the ceremony, where guests are asked to leave the photography to the hired professional and to just sit back and enjoy the ceremony, gadget-free. An unplugged wedding also makes for a more intimate and memorable ceremony for the two of you, as you will have a greater emotional connection with your family and friends if you are able to see their faces instead of a sea of electronic devices that they are holding up!
Additionally, guests should not try to shoot alongside me during the formal group portraits. If they do, the individuals in these photographs will be looking in different directions (some at my camera, some at the guest off to the side), which may not be obvious at the time but is very noticeable in the images. This also makes these photographs take longer to complete than it otherwise would.
Lastly, if you have a friend or relative who is an enthusiastic amateur photographer or perhaps an aspiring professional, you should discourage them from using your event as a portfolio-building opportunity, as their efforts to "get the shot" will likely adversely affect my ability to produce the level of work my clients expect. In short, ask that they respect the substantial investment you have made in hiring a professional photographer!