nef, it's got nothing to do with redressing a balance. The airlines will go to the airports that are in their best commercial interests to serve, end of. Airlines aren't charities and are not under any obligation to take their business to certain locations.
I would love to see ABZ and GLA grow their scheduled European flights profiles. The fact that EDI has been able to do this in the last couple of years is not as a result of alleged monopoly abuse by BAA, nor is the growth there some underhand conspiracy against ABZ and GLA. Such suggestions are tedious and wide of the mark. GLA has historically dominated the market to Florida and various other leisure destinations, and in the same way it's hardly likely to be an accurate reflection of the geographical spread of demand in Scotland for those destinations either, but it's just the commericial reality the airlines are dealing with.