It's not a party because they don't include popcorn?
Well I'd be more happy at havnig my friends around than having food. Not that I'd not get them any, but I just think the fact they are there would be more important is all.
Still, they are giving you some free stuff. If you're that worried about food you can buy it and then cover it with the £10 voucher.
Anyway each to their own and all that