There are many ways to play Entropia.

Some people see it as pure entertainment and/or social, and are happy to "throw away" some of their extra cash on their favorite hobby to have fun with their friends.

Some people treat it as gambling, doing high risk stuff looking for that next ATH (I don't recommend that)

Some people put a lot of thought in it, try to play as economical as possible, and "beat the game". If you're really patient, there is even a way for constant but slow profit, collecting "sweat" (a basic and highly sought resource), which is free to do, but very slow.
Try come up with theories, and enjoy discussing them, to try get an edge.

Some people try to provide a service to other players.
This could be anything from collecting resources for crafters, be a "hired gun" or medic, arrange events and competitions, teach newbies the way of the game, arrange sight seeing in the world take people to new outposts, make art, decorate apartments, or design clothes, or do avatar modifications. Only your creativity is the limit.

Some people treat it as an investment, buy Land Areas, Shops, Spaceships, and other sure sources of revenue, or high end gear and skill, and hope it will give them an edge.

Most people are a combination of all the above, and more.

The great part is that you are free to choose exactly how much you think its worth to spend for it, and when you tire of it, you can take most of it back out, or with some luck and "hard work" a bit of profit.