I tried to book a flight where the cheapest seats were £6.
Ditching that I went to add a bag, and on doing so I realised that adding suitcases on their own cost more than "leisure plus"...
I think they are pathologically incapable of being straightforward to deal with, in the same way as BA are pathologically incapable of going a certain number of bank holiday weekends without people camping in Heathrow...