To be fair, maybe they aren't deliberately discriminating. Advertisement isn't free, so with a limited budget you will want to optimise your ads for conversion. That's marketing 101. Maybe they think (or even have evidence to support) that a specific demography has a higher conversion rate. For example, the reasoning might be that there are more programmers amongst younger people. It would then be inefficient to advertise to other groups.
Sure, there is a grey area here, but the intent might not be as malevolent as implied.
I think they'd have to be pretty stupid not to realize the effect of their choice here. I'm all for Occam's Razor, but this is stretching that line pretty thin.
Sure, there is a grey area here, but the intent might not be as malevolent as implied.