I agree, seems a bit rich to charge an ILS fee (£13.20 - £26 if over 3 tonnes) for a non precision GNSS approach. Cambridge isn't cheap in the first place - £25 for a visitor GA (£35 if you are over 2 tonnes - 3 tonnes), it's £9/tonne/day for parking and they charge £10/day to park your car! Anything above 3 tonnes, the landing fee id £29/tonne which is steep.