We are aware of the issue with the badge emails resending to everyone, we apologise for the inconvenience - learn more here.
Dropbox client for MacOS should be available at the App Store, not as a separate download.
All major software packages use App Store. This is more convenient for installation and updates. It is safer for general users to install software from App Store that to make random searches on the web trying to find the client, and it is more likely that users ignore scam emails suggesting updates or upgrades that may potentially install malware instead.
