That's pretty convincing to me

From now on, you only pleasure half giant

Yes, the beard hasn't a home, but the man does.

When the alternative is staying with a family of assholes, maybe leaving with a stranger isn't the worst decision.

Well, he also gave Dudley a pig tail and start a fire with his umbrella, so that makes it considerably more believable.

His beard does have a home - on his face!