In this age, most videographers rely on DSLRs (the same type of camera photographers use to do their job) for shooting video. So it is logical to think that there may be videographers who could also provide stills. The answer, as many times, is "depends".
1.- Video and Stills are two separate modes on the camera. If the videographer is constantly shifting, she will probably miss some of the best parts of the event or the "performance".
2.- Video modes are -in general- lower resolution than stills, even when coming out of the same camera. Even HD video equates only to a 2 Megapixel image.
3.- Everything aside, Photographers and Videographers are looking for different things. Videographers think in sequences, they build a story. Photographers are saving a moment in time. Each frame in a video is conceived to be seen in-relation and in-sequence with the adjacent ones. Stills are conceived to be admired for minutes, to be "hung on the wall".
This couple was wise enough to recognize the benefits and I got to work with good friend and Videographer extraordinaire Diego Pocovi.