These type of people receive a short term gain through their manipulation of the system, but are usually "found out" and then shunned by their peers in the long run. It is a self governing process and the PDGA need not waste their time and energy on this non issue.
There are two elements to this, in my opinion, both PDGA issues.
One, what if the person manipulating the system could care less about being shunned by his/her peers? We may think, "Oh, so who cares about one guy being a jerkface? That's his business." But the PDGA should care, because this does happen regularly, the intentional DNF. If it happens regularly, it has the potential to grow into a bigger issue, as more people may decide they want to manipulate the system. And when a touring pro does it, it pushes the boundaries further. The fact that it occurs, in my opinion, is a burden to the integrity of the game, and that should be something the PDGA seeks to preserve and move forward.
Two, without any policy to govern the issue, the jerkface can still register for, play in, and DNF during any tournament he/she wants. We may think, "Oh, well, jerkface doesn't get his money back anyway, so it's not a big deal." But the PDGA should care, because this is the jerkface that is carded up with other non-jerkface, honest players who may have a diminished or less enjoyable disc golf experience, or who might lose a realistic chance to win a tourney because of a bagger (yeah, I know it's not tee-ball where everyone needs a trophy, but...). And that should be something that the PDGA cares about, because it's again a burden on the integrity and forward progress of the game. We may also say, "It's more of TD issue." But shouldn't the PDGA, which sanctions the tournaments, have policies that make it easier and more straightforward for TD's to run their tournaments, so that the jerkface doesn't ruin an otherwise solid tournament for a bunch of players that might not come back because of it?
I personally think the intentional DNF is a suck move, because I'm not the type of person who would ever bail on a bad round like that. But I think it's at least smart for the PDGA to look into possible policies for the situation.