I was recently watching a documentary on nature photographers and noticed that they frequently fired off dozens of frames in very rapid succession when taking their shots.
They then indicated that they would go through their shots to find the best.
As far as I understand it, there is no difference between the digital light sensor used in still photography and digital video, so what would be the advantage of using a still camera set to "machine gun" mode, rather than taking a short video and going through it frame by frame?
There are at least four reasons.
First, although the same sensor is used, video generally uses only a portion of it (either by skipping lines or some more sophisticated method). 4K UHD video is the equivalent of about 8 megapixels. Most DSLRs these have three or four times the pixel count, and many have even more. That means it's possible to have higher resolution images (and possibly crop more tightly).
Second, video is usually compressed frame-to-frame, and the image quality requirements for any given frame much lower.
Third, you almost certainly want to be capturing RAW data — "uncooked" data right from the sensor. While some high-end video cameras can capture a raw video stream, most don't — and, even then, it'd be a huge amount of data.
And, fourth: video typically doesn't give good control over shutter speed — and is limited to electronic shutter.