Hello David,
Since putting in this comment, Webroot responded to me that they had seen RU used as a hacking tool, and that's why they were treating it that way.
That was a lazy answer. Just about any remote access tool can be used (and is used) for malicious purposes. Our legitimate and digitally signed files have nothing to do with patched builds or various other malware builds (such as droppers, loaders, etc). Isn't it the job of antivirus software to stop such malware?
Instead, they just found an easy way and decided to block the legitimate files too. You can write them that and ask them to do their job instead of trying to save their time by abusing legitimate software such as Remote Utilities.