I think you are being deliberately obtuse and disengenious by comparing working folk like teachers to the idle class of royalty, it won't wash.

It "washes" very well Jim. I fail to see any difference at all. The Wilsons, the teachers I mentioned, when they gave up teaching and lived off the profits of their property portfolio (income from the rents they charged), they did exactly what the Government/Exchequer and the Royal family do in relation to the Crown Estate, Duchy of Lancaster and the Duchy of Cornwall - no difference at all apart from scale:

Property portfolio worth £X generates £Y in income.
Property portfolio worth £X incurs expenditure £A each year (That £A will include whatever income is derived from those administering and managing the properties).
Profit from Property portfolio = Y - A
Tax income derived will consist of:
Tax from the net profit
Tax from those taking income from the profits or from wages paid for management.

In the case of the Crown Estate, the Duchy of Lancaster and the Duchy of Cornwall roughly upwards of £360 million in tax to the Exchequer each year.