> all my EU/UK macbook plugs I got from apple are always grounded, metal prong and metal side pins

The short version, where you remove the extension with the 3-prong plug and attach the plug directly to the charger brick, is only available in 2-prong in the EU/US (the UK thankfully still gets all 3 prongs in this configuration)

UK plugs are always grounded because there is no ungrounded version.

But elsewhere you only get grounded plug if you buy extra extension cord for the apple power brick, otherwise it's only ungrounded.