Yes, there is a great online service for removing background from videos. I recommend you to try Depositphotos. It provides quality results. There is a free trial version on the website, but you will have to pay to get full access to the features, of course. But in my opinion, the results are worth the money. I was personally happy with the results. The tool works pretty accurately while maintaining the quality of the main video. But as always, it's better to try it yourself on the free version to be sure.