It just gives up that data to anyone that asks? Seems like a huge privacy issue.
Imaging Apache or Nginx giving up the last 600 IPs it served and maybe the URLs they went to.
edit: there is always the occasionally open Apache /server-status handler that leaks this type of data.
I could do a nmap on the public internet and probably get a similar amount of addresses. An IP is about as "private information" as a phone number nowadays (You know, those things that get sent out en masse in yellow and white books for public consumption with real-life names next to them).
So you synced your time with a server. Why would anyone else care about that? Why does it matter if someone else knows you're syncing time?
This is a very different service then a web browser.