CY: The US has the same regulations. Or some what similar. When I got my EPA card, we were told that if the system has less than 50 pounds of refrigerant, it's legal to keep topping it off. Might be expensive and impractical, but it's legal. For household refrig, I don't have any moral problem with adding a couple ounces. I can imagine that many techs would want to go the recovery and leak check route.
CY: You can also check for heat on the condenser coils, that's a good indication of charge.