A month or so ago I was stuck on a problem and thought I'd go through a tag for something I'm familiar with, and submit some answers to try and get enough points to be able to fully use the site.
One answer had a new programmer following a tutorial and using an old method signature. I commented that the tutorial he was following is out of date, and listed the correct method to use.
The person downvoted my answer, and then pasted (basically) the same code as the answer to his own question and accepted it. I know I just had bad luck in this case, but it's pretty frustrating.
Not allowing a user with low points to do some functions makes sense, but let them submit content and allow other users to determine if it's useful. I could have (and wanted to) comment on dozens of answers, which would of helped out a lot of people and saved them time/frustration.