Entertainment
In my opinion the best way to stay happy in PE is not to think about it as a way to earn money, but to think about it as a form of entertainment.
If I go to the movie and pay $15-20 with popcorn and the drink, while enjoying (and sometimes not) it only for 2-3 hours, than in contrast, for the same money in PE I would enjoy the time much more and longer than that.
Just $20 a month would bring exciting hunting and mining with some unexpected items in loot.
More to that, we communicate, there are people to talk to and there is always something to talk about. We are not alone. (Yea, get that from the movie).
Sure some would come into the game with the hope and the desire to make money on the rest of the players (which makes the game more expensive to play) by doing only trading and exchanges and not much than that.
But in general, I find PE involving and pretty exciting.
We can make our own decisions within the game on where to hunt, what to buy etc... this is not a dumb shooting game like many out there and $20/month that I am putting aside for this game to spend would be a little contribution to MindArk for the job they do to keep this virtual world alive.
If you do not expect to earn but just enjoying the game as it is - you will have your reward and would not regret it, I am sure of it.
And BTW I just got my first 107.00 PEDs HOF today...

which brings my expenses for the last week into a balance of almost zero. So I had a free week of entertainment...