What is the deal with firefly studios?
Why not Stronghold: Crusader Extreme, which includes the original if I'm not mistaken.
Firefly Website - Stronghold: CE

It includes the original Stronghold: Crusader, but not the original Stronghold.

Yes, but the question still stands, why not sell Stronghold CE instead of Stronghold: Crusader.
I was referring to the announcement of the latter, not the releasing of Stronghold.

I think these are reasons.
1. It's sold 29.99$ from another store, as gamersgate. If Firefly don't cut the price there, they might not allow gog 9.99$.
2. [Stronghold : Crusader] got good reviews at then, but [Stronghold : Crusader Extreme] got very terrible reviews. I don't know detail about [S : CE], just know it had terrible reviews, and will go away & never touch it.

GOG seem to sell old games, Stronghold Crusader Extreme was only released last year, whereas Stronghold Crusader was released many years ago.

Gotcha.

The only reason SHCE got bad reviews (and it only got a couple reviews, period) was that reviewers can't seem to realize what it was. It wasn't a new game, it wasn't suppose to be. It was a rerelease of content that wasn't available worldwide with an added bonus of the Extreme modification of the game. Never, EVER was it marketed as a new game, and so the pitfalls the reviewers give it are stupid and moot overall.

from quickly reading some reviews I would agree with what Magnus says - that Extreme was more of an enhanced version release rather than a full new game.
I suppose some of the "bitterness" in reviews came from the fact that the added content was not released as a patch or expansion and rather required one to essentailly buy the greater part of the game again.

Personally I hate Crusader Extreme. The timed unit addition, and the attack bar (that charges over time) completely ruin the game.
This is an RTS, not an arcade game!
That said, if it were possible to use the high unit limits but not any of the other 'enhancements' I would be all over it. But nope... no choice in the matter.

well i think that the timed unit addition can be removed(i believe its a map gimmit), so you can play regular crusaders but with the new AI, and 10k unit limit. ;)
its seems that all you gotta do i make a new map without those weird unit spawning barracks...(or mod the old ones).