Currying is a form of higher order function, and it's not necessarily preferable, but often just makes sense.

I think it is in some way overused in Haskell for example. When your function takes five different parameters, it's unlikely that the curried style really makes sense, other than that it's just convenient and idiomatic in Haskell—in many cases you would be better off using a record type for the parameters.

But if you consider for example the map function, it really makes sense to consider it a higher order function in a "curried" way. That is to say, map f makes sense on its own, because map takes a function and transforms it into a function that works on lists.

So the type

    map :: (a -> b) -> ([a] -> [b])

is really nice, and nicer than the uncurried alternative:

    map :: (a -> b, [a]) -> [b]

Of course they're isomorphic, but the curried one seems to definitely win in terms of elegance, and you avoid ever having to type

    \x -> map (f, x)

or similar.

I think if Haskell had really convenient named parameters, people would use currying less, but we'd still want to use the curried style for many functions that actually make sense as higher-order functions.