Because the C-store is the way this company keeps this game afloat. Why would they put anything in the game that you could get by chance or a bit of grinding, when all they want is for you and me to pay them cash for the items from the Cash Grab Store?

Wait till they put content in the C-store. IE: You want new missions? Fine, pay up.

"The sky is falling! The sky is falling!"

No...but you're being fleeced.

Somehow, I doubt that. I have yet to spend a single dollar in the C-store, and I don't feel my game experience has been negatively effected by this at all. I will in the future, but so far nothing. Nothing in there has any effect on the game you're playing. A different model for your ship, a different uniform for your character. It's just wrapping paper. The game is unchanged.

That is unless you want to play as a caitian, a pakled, a klingon (as a fed char), a ferengi, or a rigelian, in which case they aren't just wrapping paper they have unique in game traits, that effect they're gameplay.

Additionally the Galaxy-X cruiser (and surely the soon to come excelsior t5) have different boff setups and other special abilities that also effect gameplay.

Frankly I think they have gone against their "nothing with gameplay effect will be available on the c-store that isn't also available by IG means" statement they made when the community was ready to write them off as being setup to make as much money as fast as possible, then cutting and running.

With the exception of the Rigelians, which I am completely unfamiliar with, all of those races are very rare in Starfleet. Having them as C-store options allows players who desire them to play those races, without making them exceedingly common. Consider it a compromise between fun and canon.

The Galaxy-X is only there because the players requested it. It was intended as a reward for the referal program. The players asked for the option to buy it right out, and Cryptic listened.

None of this shows the slightest indication that they will ask for money for content updates. Or that they will "cut and run".

.... except that all the extra species, uniforms, ships, and emotes are just flavor. You don't need them to play the game whatsoever. They are extra. And their unique abilities aren't really game-shatteringly revolutionary or anything of the sort.
The new T5 retrofits? Already get them in-game, just gotta make the grind to VA1.
The Federation Dreadnaught is a point of contention, however it's a slight one. The ship is powerfull yes, and it was originally created as a prize-only ship. The community whined so badly that they wanted it in the C-Store, and BAM, they got it. It's never gonna appear in-game otherwise, considering it's alt-world origins. So really, it still is kinda a somewhat-exclusive obtainable. Honestly, I'm fine with that.
But, the only time yer gonna see content you have to pay for is with an honest-to-God expansion pack, but even that's debatable. Cryptic's already stated that they're gonna make all the in-between updates, Seasons, and everything that falls under that free. Several times.
Sorry, OP, but second poster is right in his observation. Troll attempt: fail.

except that they are making you pay for the new tier 5's they are making, and it is a slippery slope, you start charging for one thing, and if people pay for it, then you start saying to yourself "Hey, they paid for X, i bet we could get them to pay for Y!"

Slippery slope is a logical fallacy, not a proof of intent.

Or an awesome gentlemen's club in southeast Asia.