Expanding HopelessN00b ♦ comment:
In SE-Universe, comments are second class citizens. Unlike question and answer, they aren't searchable. And they can be deleted anytime without any warns. Snippet from ServerFault help center
Comments are temporary "Post-It" notes left on a question or answer. They can be up-voted (but not down-voted) and flagged, but do not generate reputation. There's no revision history, and when they are deleted they're gone for good.
Of course only SE-developers can implement feature like Helpful Comment. But it will contradicts with the nature of comment that can be deleted without any signs.
PS: If you want to know total votes on your comments, see this query on data.SE
I propose that as I think that comment on server fault does not have the same value as on like stackoverflow. Some problem are hard to diagnostic if the user does not give enough detail, even with detail sometime, and a comment can easily lead to an actual answer. So we will not "reward" users with points that help with comments, but the statistic would be show.
+1 for your argument about the comments. Sometimes I'm too lazy to elaborate the answer in proper section (because browsing via mobile, etc). So I put some suggestions in comment and let OP clarifying if it is working solution. Because of Server Fault nature, we can't replicate the OP's problem exactly in our environment. Comments system help us get clarification (and/or troubleshooting steps).
