Is it wrong to avoid paying tax?

The Queen?

Does anyone NOT pay a window cleaner cash in hand?

OMG ...I pay my window cleaner cash in hand. Perhaps though I'd better not admit this on a public forum. Does that mean I'm acting illegally or is the onus on Rob to declare his earnings, pitiful though they may be.

He's in exactly the same position as those who squirrel away thousands of pounds in off shore accounts I suppose. But I'm sure his accountant has explained that to him

I Fink!

Well I avoid paying tax every year when I use my full ISA allowance.
It goes some way to mitigating the taxes I pay on just about everything I buy.
For example, I have a cleaner once a fortnight. I pay her out of income which has already been taxed at 25%.
She works full time, through an agency, so pays tax and NI on her earnings. The agency employer pays employer's NI and has her profits taxed too. Oh and the government charges VAT too
I could of course evade tax by paying for a cleaner cash-in-hand.

It's evading tax which is illegal and morally reprehensible. Is paying for services cash-in-hand very different from people evading tax by off shore accounts and dodgy accounting practices?