I'm not ignorant to the way much livestock in the world is treated/fed/etc. and I'm aware of the US corn lobby, for example. But coming from Ireland I'm still constantly surprised at how unusual people seem to find grass-fed cattle.
"Grass-fed" isn't a term we use / recognise here, because... it's implicit. Kerrygold is the mass-produced, big-brand butter, and yes it is grass fed. Just like everything else.
That said, this makes me curious about the other listed brands. I'm assuming grass-fed is the norm (northern-?)Europe-wide, so most of the above (being French???) should also be?