That's like saying integers are an optional thing, and it's no big deal if your programming language doesn't have them. True, they aren't necessary (look at peano arith or pure lambda calc) - but it sure makes things a lot easier. It's much more concise and intuitive to write some search or divide and conquer algos recursively than imperatively.

javascript doesn't have an integer type.

Possibly it makes things easier for some algorithms, but as I said, it is optional. It's not rocket science to rewrite any algorithm that relies on recursion to not need it.