>Part of being liberal is the freedom to adopt any legal practices that makes you happy. //

Yes, sort of.

Let's take a slightly extreme example - liberal societies outlaw slavery. Suppose I come to France and want to keep slaves; how hypocritical of the French to talk about liberté and not allow me to keep the slaves that I wish to keep.

I'm not sure it's true hypocrisy; it's just a innate part of liberalism that there are limits to the liberties allowed.