I handle a lot of video for my company, a lot of them are confidential (Just schedules of upcoming stuff, nothing else don't get the wrong idea). I usually keep them on an encrypted drive. So lately the company started using this quality management software and they've asked me to keep files the file management system with it. (ie, in the cloud.) So this concerns me. How easily could someone steal those files? Or shouldn't I worry?
get your own NAS and keep it at your house. Then you don't worry if DropBox, Google Drive, etc. will steal your data.
IF someone has an admin and and password to get into your NAS that is on the web, then they can steal the data - encrypted or not. Just like I can steal your money into my account, if you give me your name and password to your on line banking account.