Possibly so - I don't have numbers, but I'd estimate it's going to be in the hundreds of millions per year on average - this is however very small compared to the ca. £600 billion total annual tax take.
DoW inherits £9 billion . . . . all tied up in trusts. 40% of that is a bit more than hundreds of millions.
off shoring is estimated at £5bn . . .a quick google estimates anything between £30 and £90 bn a year is 'missing' in tax revenue . . . . surely its worth investing in clawing some of that back.
or maybe not if you have fingers in the same pies. and get on well with your 'mates'
the bottom line for me is that inequality is increasing daily in this country and most people are blind to it. How long before the revolt or the revolution. we're clearly a pretty ignorant/tolerant bunch looking at this years activities