Guests should not be allowed to leave to Leave Reactions on this site.
I have a guest stalker on here and they just follow me around the forums to leave a disagree reactions. I am sure it is the same person because I get a disagree on anything I post even when the comment was not even a disagree or agree type comment. Why I think this is the same person every time is because when I post anything and watch the post for a reply it always say 2 people view me and a guest user. Right after I get a disagree the guest user is gone. I find it rather annoying, but since you can't do anything about an annoying guest user trolling you I kind of just try ignoring it.
Not sure how others feel about guests being able to leave reactions, but me personally, I did not find it a problem and actually kind of found it fair until this where I realized guest users can abuse this little perk just to be annoying.