Standard benefit calculations
While it's possible that the excessive number of requests is from public access within their LAN, I can just imagine the position: there is a purchased bit of software which the benefits staff have continual problems with, so one of them says "hey, this one on the web is better than the stuff we have in here".
Actually this highlights the fact that many of these standard council functions could be better met by consolidated web enabled services rather than hundreds of councils all going through an IT procurement process. Entitledto.co.uk have missed the point - rather than presenting Derby with a retrospective bill, they should have offered them a pay-per-use online benefits calculator.
Alternatively, if their benefits calculator that good, I suppose it's too much to expect central government to pay them to develop a FLOSS set of software which councils could use without paying further software royalties?