Yeah I completely understand what you're saying Abomination, it seems almost useless because it's 1 character. You could just do this with JS or a simple conditional statement in the like.php (assuming that's the file).
I personally am not bothered about it, but I suppose pedantic people pick out these things and it would look better/professional. It's amazing what things people can judge things on.
@Disjunto, but then when there's 4 (standard 3 + 1 other) there's still going to be one other, unless you remove the 4th one when the 5th person likes it.