Re: claim their VAT back
>unless they produce "zero rated VAT" products, of course, but have to buy goods and therefore DO claim back the VAT they have paid.
Not sure of your point AC, but such businesses still offset it against the VAT they have collected, just that for these businesses the net VAT collected is likely to be negative and hence HMRC sends them a cheque.
HMRC sending out cheques to those with negative VAT accounts helps to make it remunerative for businesses to claim back VAT on expenses. As HMRC don't send out cheques if your level of expenses exceeds your post-VAT income...