I don't think the creators of angry birds said: "Let's make a game like Crush the Castle but with birds", it's mostly the same but they probably got the idea not even knowing that Crush the Castle exist, it's not a rip-off, im not saying its better either, but is really good.
That's like saying the main reason Black Ops is different from Halo is because one has AUGs while the other has plasma rifles.
Not really, considering that firing any gun is pretty much a universal concept (pull the trigger, bullets/plasma/other comes out). Where as catapults and slingshots are 2 totally different means of launching projectiles; catapult you cut a string, the mechanics in it does the rest, while with a slingshot you pull the sling back (along with the object) and release.
But I don't think it's a ripoff of CtC. It works completely differently; it's on a much smaller scale, stories different (also included in the term 'ripoff', the birds fly slower, not as many options in Angry Birds, Angry Birds has more levels (the new version), and Angry Birds I also find to be harder than the newer CtC games because you only have so many shots while in newer CtC games (meaning since Player's Pack for CtC 1) you can take as many shots as you want, just depends on whether you want a medal or not. If people should be considering anything a ripoff, it should be Siege Hero. I like both Angry birds and CtC and think they're both enjoyable.
BTW, if you hate angry birds or crush the castle, just don't play it.
P.S.:Angry birds sucks.
That is a huge confliction. You say sever yourself from either game if you don't like them, then you come to a thread about Angry Birds just to say it sucks. You also say that it's a ripoff, yet you gave no reasons as to why. Same with Angry Birds sucking. You gave no reasons for that statement, either.