Nectar

And if you disagree with a statement, but you respect it, again the best you can do is press 'like' to avoid permanently tainting their reputation :?

Just depends on the people, and how they view things. Another option is to just ignore it.

I don't really agree, to be honest - I think they can be put to good use at times, though only if given out extremely sparingly. I think I've personally given out about four or five (as compared to potentially thousands of upvotes), and reserve it for things that I disagree with to an extreme.