Hi,
Who will know if you dont tell? its only butter, its not as if you are trying to take a pig or a cow
I take things with me when i go abroad (bacon, lurpak,sausage and other stuff) i have never been stopped.
If you do take some, wrap it up well because it tends to melt before you can get it in to a fridge, and you dont want your clothes to be greasy.
Loulou