In Python, you can easily define methods within methods, so there is little semantic clutter at the toplevel.

  def doSomething():
    def doSomethingElse():
      # Code goes here.
      pass
    
    eggs = filter(doSomethingElse, spam)
    for cheese in eggs:
      # Do something.
      pass

There is no big harm in giving something a name. Giving a name also helps if you find a need to reuse it later. Plus a name can give a hint to what this code is for.

Yet, if you look in functional programming code (e.g. Haskell, Scheme), you'll find many anonymous lambdas (that in python would be > 1 line). Why would good coders bother doing that?

If something is small and enough to be anonymous, it's usually simply enough to be expressed without binding a variable.

(See point-free style.)

Obviously. Show us how to do point-free style in Python. We're talking about Python's lame implementation of anonymous functions, not something that it doesn't have any implementation of.

Oh, I thought you were talking about programmers' habits in Haskell.