Helicopter Pilots rarely get to use paved Runways....that is not what we are about.
I challenge you to prove your statement that it is impossible to identify a grass runway with 1500 Meters of Visibility or less.
How do you reckon that to be so?
Your 1500 Meters roughly equates to One Statute Mile.....which is adequate Visibility for a Helicopter (especially with the advent of GPS which makes finding the Airfield ...even if a grass runway).