We are currently looking at nursery for our DC and quite a few locally charge a top-up fee for funded hours. When we queried this, they said it was because the rates paid for by the government via the councils are too low.
So, I asked our council what they pay, and it's pretty much the same rate per hour as most of the local nurseries charge normally - which would usually cover their costs.
I'm hearing nationally many nurseries saying they will close if they don't charge additional fees but it seems that some are profiting by getting their full funding and top up fees. I understand that each nursery is a business and they want to make a profit, but I wish things were a bit clearer from them about why they need more.