So if you ask, which greed and addiction will be a disaster? the answer is that both will lead you to disaster. It is important to control your emotions when gambling so that things like this can be avoided. If there are any signs that you are headed there, then you need to advise yourself. Because a responsible gambler is someone who can advise himself to gamble within his limits and not force himself on something he cannot control.
I have also the same answer, both are disastrous.
Greed and addiction leads to both ugly results and that's why if you're going to compare it, there's no difference with these two and one gambler having any of it will still have a bad ending with whatever bet they would do.
With control of emotion, you might able to see things very easy as you know yourself better if you're still in the right mind and you can feel that you're greedy to avoid being addicted.
Even not with greediness but with wrong decisions, you can still end up disastrously with how you do your gambling sessions.
Greediness at least can produce some positive outcomes, as a person that is greedy will try to find the most efficient ways to do anything so they can increase their profits, which in return makes society more efficient as well, however I have yet to see a single good outcome coming out from an addiction, and even if a person learned a lot after going through a period of addiction, those are lessons they could have learned anyway and without having to suffer as much as they did when they were addicted.