Jon, Jon, Jon...
That would be OpenCandy, the official SourceForge ad/spam/crapware, and that is OLD news. I was, I admit, unaware that FreeFileSync opted in, as I prefer rsync myself (command-line utilities are not known for spamware...) but it doesn't surprise me.
I suggest you try the PortableApps.com version, or there should be a way to uncheck it in the installer.
I must say I am extremely disappointed though.
While the program should work as well as it ever did, I cannot in good faith condone supporting such garbage.