The filler that they choose to use in the pad material is good for keeping brake noise down. Brake squeal is a significant problem for vehicles under warranty (it costs manufacturers and dealers $$, and ticks off customers) so using a pad that is quieter is a business decision for the initial factory build. The vehicles don't necessarily stop better than a pad with a different composition. The factory pads do have a good balance of low noise, performance and cost, just at the expense of dust.

I have seen low dust pads from BMW on newer models (2012). Finally we can dispell the notion that black brake pad dust is a badge of honour.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue