If you are in it for the money don't bother going to the Bar: there are significantly easier ways of earning comparative or even larger sums of money, ie in a law firm, merchant banking, or stock broking. The Bar is a way of life- a vocation rather than a job. You will find the majority of entrants to the Bar especially in criminal, family and general common law will earn significantly less than people with comparable qualifications at City law firms; and the early years the work in such fields can be a matter of being sent all over the country to pursue small pieces of advocacy.
That said there are a number of Chambers especially in the tax, chancery and commercial fields where one will from pupillage earn substantially more than an employed barrister/trainee solicitor, there are also chambers which exempt their new tenants from contributions, or whom guarantee a certain quantity in terms of receipts. There is indeed a "pay war" between certain sectors of the Bar for pupillage awards.