foo.each do |x|
    return if x == 3
  end

The thing is, they’re rare in practice for cultural reasons.

What are the "hacky" methods currently used for packaging you mentioned? The only methods I'm aware of no longer work or still require a separate runtime.

In Ruby iteration is implemented by letting something call a block repeatedly until the end of the iteration. The interpreter provides jump points in order to implement skipping or breaking the iteration. A continue is implemented as a form of jumping to the end of the block, a break is implemented by jumping past the call to the iterator function. Without the return it would be very awkward to return something from the function.Imagine a function that returns the first even item from a list:

    >> def find_even iterable
    >>  iterable.each { |x| return x if x % 2 == 0 }
    >> end
    => nil
    >> find_even [1, 3, 5, 6]
    => 6

    >> def find_even iterable
    >>  done = false
    >>  rv = nil
    >>  iterable.each { |x|
    >>   if x % 2 == 0
    >>    done = true
    >>    rv = x
    >>    break
    >>   end
    >>  }
    >>  rv
    >> end
*

Blocks are pretty much an iteration construct.

It's really not that confusing.