I thought about that, and then realized, the only reason that it was so obvious, is because those in the WH who released it, appear to be unaware of the final, important step. If they had simply printed out the PDF, and then scanned it into a new PDF, all the anomalies would have been removed. The problem with the document, and why it’s so obvious, is that they uploaded the working document, and that could have been a miscommunication, and not pure incompetence.
They may have been nervous, as well. Since this “document” was only put together after Trump made a big deal out of no birth certificate, they whipped one up in a couple of weeks, so were likely not being very careful.
But the smiley face clearly points to other motives, perhaps “in your face” snark, or other as mentioned above.