Very good topic Nil,
Since its a service exchange in contractual terms, deciding the contribution is left to the parties agreeing for the same. Most of the private consultancies who does not have much backup companies with it do this, and infact many collect the salary fixed amount even before the candidate joins and gets his salary.... and as I have observed, many the candidates placed by him will be chosen on probation or trainers, and few are from background entry, and there employment is not guaranteed.... there are genuine consultancies also, but I suggest the candidates to believe in and rely upon those consultancies which have the company backups or agreement withe the companies for placements.....most of such consultancies hardly collect any fee from candidates as they will be getting there pay from companies hired them for sourcing candidates.........