Nobel. do you mean that the 'state school' system does not have enough money to go around .
However, think of it this way if a village Brownie/Scout group could not get a piece of Gymnastic equipment paid for by Sport England because the budget was being spent on Max Whitlock/ Louis Smith.
Is it correct to spend the money benefiting the 'elite' over the majority.
This comes down to whether you believe everybody should have 'Zero' chance or the most gifted should have a reasonable chance .
The only definite conclusions that can be drawn when comparing grammar school numbers of FSM pupils with other schools FSM numbers is that grammar schools have very low % of families who don't work a full time job at least (37-40) hrs PW either by one parent or combination of two.
We know that because they do not qualify for FSM
However, we do not know (except by conjecture ) what the median income of a grammar school family is !.
Because we can not answer that question ?
Therefore assume family A
have a family income of £20K pa (father has a drinking problem , mother has mental health issues) child passed the 11+ . Are they an advantaged family .
Family B have an income of £14900 PA but live in a stable and loving environment DD failed the 11+ .
Which family is advantaged/disadvantaged ?
This highlights the 'stupidity' of using 'money' (absurdly low one at that) as the sole basis of judging advantage/disadvantage.