CRB checks....where to stop?

I saw an article on the evening news about the CRB checks that are now "supposed" to being implemented to ensure the safety of children.
This might be controversial, but when an individual gives their time freely, without recompense, they should not be required to pay for a CRB check.
I have 4 of these, and one was gained when I was working for a registered charity. I gave my time freely, but it put me into regular contact with children who were not my own. This was before the big CRB push, the charity managed to find funds to put all the trustees through a CRB check. It was not compulsory, but at the time a CRB check was not the price it is today.
My point is, if the government wants people to have the checks, they should be cheaper to run, or there should be a body that provides the finance for charity/ voluntary organisations. It is wrong to ask these people to dig into their own pockets.
Another thought occurred to me, where is the line going to be drawn. If parents giving other children lifts in their cars will initiate a check, what about when children have parties? Will there be an inspectorate set up checking that the correct adult/child ratio is maintained, and that the adults have been cleared?
Also...who will pay for these checks?
My daughter works in the leisure industry, sometimes parents will leave their children where she works to entertain themselves whilst they do another task, like the week's shopping. Do these places need checking?
Also, travelling fairgrounds?
To me a huge can of worms has been opened. Will anyone who occasionally babysits have to be cleared?
Don't get me wrong, I am all in favour of keeping children safe .....but where will this all stop? Your sister/brother needs their child looking after, alongside yours....you have to refuse as you don't have the regular paperwork? I really don't think this has been thoroughly thought through.