(Please mind that there has to be a strict relation between a minified code and a plain source code provided at some repository. This is not true, at least in terms of the resources needed to verify this and the probability of this being covered by average budgets, for binary codes. – Recommended reading: "Reflections on Trusting Trust" by Ken Thompson)

Edit: At best you're winning a year's worth of Moore's law in performance and are paying for it in terms of page load. On the down-side, binary code is just as bad an idea as e-voting: You're putting the interests of your users against literary trillions of dollars of interest in exploiting the system (yes, the leverage would be enorme) – and if the worst has become true, it's already too late to revert.

As for the real-life example given above: The third party is billing the client only a few bucks, since the real business is in profile building and exchanging profiles. So, are they expected to hand out the source code for 5 bucks or so? Probably not. Who is to lose? Everyone visiting the website.