Locally never. I have 3 or 4 shops that know me very well where I fill both air, EANX and stage. It even goes further, my tanks are not marked in any way (unless you take the oxyhacker fun stickers 'THIS IS NOT YOUR TANK', 'VOODOOGAS', etc
)...and there is no 'proof' whatsoever that they are oxygen clean... but they know I take good care so they fill.
On wreckdives... normally also not. First wreckdives you go with an experienced 'old hand'... who shows you the ropes and introduces you to the 'network'. After a few dives you are accepted on those boats you go on... and no cards are needed. It's the 'old hand' who vouches for you that you have enough experience.
On holidays in depends... good old VISA or cash + liability signature do the trick most of the time.
-Thailand : no issue no cards
-Red Sea (brothers isles): yes both c-card and log (on MV tala which is a technically inclinded vessel)
- Bonaire : c-card
- Mediteranean (Spain) : no issue no cards
- Mediteranean (French riviera wrecks) : c-card, not allowed to dive the deep wrecks without CMAS *** or technical certification
But to be perfectly honest I understand the liability reason, but on a boat as organiser or captain, just let me talk 5 min with the guy or just watch his gear and how he sets it up shows much more about experience then a c-card!?