Do you fly into Saudi ?
I am based in Saudi Arabia and I have flown in (as pax) twice recently, both times I have been issued a "immigration landing card" by the FAs. (once by SR and once GF)
The use of these cards has been scrapped by the Saudi authorities for several months now but I guess they didn't tell the airlines who will presumably carry on handing them out until they run out and request a fresh supply!
I don't suggest that you stop handing out the cards on my say-so, but if you are flying to Saudi, and still hand out the cards, it might be a good idea to check "up the chain" as it appears to be a waste of crews' and pax' time!
I have emailed GF and will try to pass the word to SR, but I wonder how many other airlines do not know!!!