I know Stack Overflow a bit (because of some of the other sites in the network). This is not really a question, but just for reference' sake: not everyone who makes minor edits is looking for reputation.
I made a little formatting edit here of which I know it is minor, but it is necessary because it messed up the code (the OP forgot a
' which makes the code run with an error!). This is
not trivial. I had to add two little words for the edit to be large enough (and I did not want to ignore the mistake).
I think it is a bit lame to reject that edit (suggesting that "This edit is incorrect or an attempt to reply to or comment on the existing post."). Especially if the question is edited in the review queue after all. Either there is nothing to be edited or there is and in that case there is no reason to reject the edit. Why would you reject an edit and then do it yourself? Or am I misunderstanding something? Was the edit already made by the first edit reviewer? Hmm not sure here.
I am used to editing regularly on a site where I have +2000 rep, so it has become something automatic. Rejecting these edits does not encourage me to edit at all under 2000 rep.
From the answers below I retain that there are several principles for dealing with suggested edits:
edits can be minor IF they deal with all the problems in a post. This explains why my edit was rejected, yet done manually by the reviewers. It does not explain why the people reviewing my edit did not also take care of the other problems in that answer.
editors really have different views. Because I was criticized for dealing only with the code problem and not with the grammar issues in the question, I revisited the question, now also reviewing grammar. Again, two reviewers thought the edit was too minor. Three reviewers accepted it. (Interestingly, the ones that accepted it have a good accept/decline ratio, but I guess that is by accident :). In the comments on the present post, the grammar was called appalling, yet for others changing it is perceived as too minor. Bottom-line: reviewing edits is subjective and democratic.
Many reviewers complain in the comments that minor edits needlessly take up their time and thus they tend to reject them. This is not communicated back directly to the editor unless he/she goes to look for it. The educative part of reviewing edit suggestions is underdeveloped. The editor should automatically be notified his edit was rejected and why. In my opinion, reviewers that edit a question based on a suggested edit, should also deal with all other problems in that post for precisely this reason. As such the editor can learn from the reviewer. After all, the overall quality of the site is in view.
I retract the following statement:
Certain reviewers have a 50/50 reject/approve ratio or worse. That is unfruitful (if not plain arrogant) and against the community policy [**edit**: there is no community policy on this, see Cody's answer].
It might be handy to check what the reject/approve ratio is for our most trusted users. A very quick check makes me believe that moderators, for instance, accept more than reject. But again, that is to be verified. As there is no hard and fast data, I retract that statement and apologize if it offended anyone.
For reviewers of suggested edits
Suggesting edits actually also takes time and effort. Please do not think that small edits that do not completely revise grammar and style (but that do fix a bug in the code) are somehow minor edits or attempts to gain reputation.