Nowadays, videos are much more attractive than regular boring images and can attract more customers in a long run. Now you can add custom video and audio files in your product instead of images, which will give more information about the product to the visitors and the chances of conversion may increase. This becomes more useful when you sell digital products in your store.
Using a video for your products instead of images might be very useful to present your items in a better way, but it becomes especially useful when it comes to digital products, such as a programmes, videogames or such, where a picture is not enough to show their strengths at the best.
And what if you sell music? Nothing can be a good preview for your product but an audio file. And most e-commerce themes allow you to add only images.