Traders and arbitrageurs are often credited with "seeding" markets with more competitive prices than would be present without them. However, Betfair's imposition of a premium charge in September 2008 was seen by some as being directed at the most skilled traders, whom it is speculated trade for a loss very infrequently and thus would otherwise pay little in the way of commission. In response, rival exchanges have pledged not to introduce similar charges, perhaps in hopes of enticing traders to move their business (and capital) elsewhere.
