Another theory in my opinion is alot of juniors advertise if they have been to a well known University (Oxbridge, London institutions, Harvard) but they don't advertise the fact they haven't and simply put LLB, LLM, etc. They may feel if people were searching the lists in order to have a good idea of someone they wanted to 'work for them' or 'work with', you may be looked over with a degree from some 'lesser institution' but as the figures in the link above show the Bar is open to people from all backgrounds.