We are aware of the issue with the badge emails resending to everyone, we apologise for the inconvenience - learn more here.
After I upload a file to Dropbox for others to download, the recipients (without Dropbox accounts) open the link and see, under “Activity”: “Patricia Johnson downloaded this file” and “Anthony Abate ...
I stongly agree. I am just starting to use DropBox to share files for a history society, and got a panicky email from one of my members saying that a file I had shared had been viewed by two unknown people. It took me a while to establish that this was not in fact the case, and now I have an uphill struggle to persuade people that DropBox is not hopelessly insecure. This is a dreadful, dreadful feature that should be removed immediately - it is bad for DropBox users and it is bad for DropBox's own reputation.