Portals have dedicated teams that can clone your game within a couple of months. This means they never need to actually take your game, and if they did, they'd replace it with their own brand if it sold well. Take supermarkets: first they take popular items then gradually replace the popular items with own-brand stuff, and slowly remove the originals. This irked me no end as I could see it happening to stuff I liked. Well, we can't fight this. I don't see any way I can make enough revenue to compete with portals.