The original had an initial purchase as well as a subscription; many of these complaints are founded in ignorance. A few bullet points:
-The Premium account gets you 500 station cash/mo (5 dollars worth), and an increase in xp/resource gains. The biggest benefit is the increase to offline leveling
-Most of the purchased items are cosmetic/xp boost, and all of the guns that are obtainable with real money, can be purchased with a type of resource you earn by playing.
-You receive certifications (a la Eve) while offline, lessening the grind for weekend warriors
-There is no other source for multifaceted, massive Air/Armor/Infantry Sci-fi battles.
-To be clear, every item that can be obtained with money, can be earned in game, you are paying to save some grind time, which isnt necessary as the game is fun.