Every day is a school day...That's interesting, I exchanged mine a few weeks ago and didn't have the screw top. Maybe it depends where you go
Twice now, I've been knocked back for not having the screw top.
Was told "it's Campingaz policy" not to accept a return cylinder without this little handle / plug.
But at the same time, I could buy a new handle /plug & then exchange was possible.
Maybe just a commercial, business policy being applied at certain distributors?