Post 1997 rates of pay for BA Cabin Crew are at current market rates.
Even that basic statement is incorrect, albeit they are much closer to norms that pre-97. But that is talking about the BASIC pay.
The main problems come in with the rest of the agreements (ie the variable pay) and the scheduling restrictions in both EF and WW.
The variable pay (WW=box payments, overtime and allowances; EF=overtime, allowances and STR payments) easily double the basic pay.
The Scheduling restrictions in WW result in cancelled flights and flights operating empty while pax are accommodated or re-booked on other airlines because of 'needing' 2 local nights 'rest'.
The Scheduling restrictions in EF result in needing numerous extra crews sitting around in case a flight arrives 2 minutes late at which point the company has to hose the crew down with cash to reduce the turnaround to under 2 hours or has recrew the cabin as the reduction would be too great (even though the flight crew can stay on board).
According to the CAA, BA cabin crew costs are DOUBLE those of the next highest paid UK cabin crew (Virgin).
Edited to add:
I know that the lack of choice of work has a lot to do with it as well, but the variablility of pay as a function of destination greatly contributes to the 20 sick days per year per cabin crew member (vs 7 for flight crew).
Last trip I flew with a purser who said she would NOT be working this Xmas. When asked if she had leave, she just looked at me and smiled.