Oh come off it!
Beatrice and Eugene are not paid to work for the RF and they are very discrete in down playing their royal status in their work lives.
Beatrice and Eugenie's private security is paid for by Andrew, which almost certainly means the Queen, since Andrew doesn't have any money of their own. It might be the Queen's private money and not Crown money but Royal finances are so shrouded in mystery (see the Queen interfering in the passing of UK laws to keep her finances secret, and the revelations in the Paradise Papers).
All the security, cleanup, and public costs for Eugenie's wedding, which includes her £250,000 carriage ride, were paid for by the taxpayer. The taxpayer bill for Eugenie's security was £2 million alone. The costs of the actual wedding (dress, flowers, etc.) were paid for by the BRF but where do you think that money came from in the first place?
Beatrice and Eugenie might be discreet in their work lives (or they may not - how on earth do any of us know?) but you do really think anyone who employs them is unaware that they are princesses? You really think they haven't benefitted from their royal statuses? In the early years of their working careers they were infamous for constantly going on holiday and barely working - do you really think their employers would permit ordinary women without royal connections to go on holiday ten times a year?
Fergie doesn't get any money from the state either and can do as she wishes.
Except that she lives in a Royal Residence.
I'm not sure Andrew receives anything either.
He also lives in a Royal Residence, and there have been numerous newspaper articles over the past year claiming he still receives a royal income. Reporters have written about the fact Andrew's finances are "shrouded in mystery" and that no one knows where his money comes from - considering his past history it's certainly unlikely he's keeping himself in the manner he is accustomed without financial support from the Queen.