Vodafone charge you £3 per day in Europe (geographical Europe, not just EU Europe) to use your minutes and texts that come with your package. (No idea if your package data allowance is included or not).
I'm assuming they only charge you that if you actually use any minutes, rather than just having your phone on.
I've opted out of that, so if I make calls here (I'm in Norway) I don't pay the £3 per day, but I will pay the full roaming call costs. I've also asked Vodafone to disable data roaming on my account so there are no nasty surprises with huge data bills.
Now I can happily have my phone switched on abroad knowing it won't cost me a fortune on the rare occasions I use it.

Not a great deal when Three offer you it for free. I do think that a £3 a day fee adds up over a 2 week holiday.

You're on holiday, turn your bloody phone off.

You're on holiday, turn your bloody phone off.

Can I use Feel At Home all the time?
Feel At Home is intended for our UK customers who are visiting one of the destinations for short trips, like holidays or business trips. It isn’t made for people who live abroad or stay there for an extended period of time. If you only use your plan in a Feel At Home destination for a complete month, and this happens three times within a year, we may have to suspend international roaming on your account, which would mean you would no longer be able to use your phone or device abroad. We’d let you know if this is likely to happen.

What's the 3 coverage like in the UK, and what about their customer service?