How unhappy does someone have to be to read someone else's serious hub, and then rate it "funny"?
Some have dry humor and others have a more serious side, do not take offense to the rating overlook it and just keep writing, There is always someone out there who may try to burst your bubble and others who will look at your work in a more unique way.
EX: In this area where you ask these types of questions, there are those who appreciate the response and others who rating them negative without really paying attention to what the response was. When that happens to me, I do not take offense I just keep responding to questions that are asked. .