Why do compact cameras always seem to involve trade-offs?

Of course — there has to be. Are you aware of the saying "Fast, cheap, good: pick two?" Any design has compromises. This isn't a "marketing reason" — it's a basic fact of making products which the market researchers must work from. And when you add the additional constraint that it must be compact, well, something else has to give.

Take a look at my recent long answer on lens design — there are a dizzying number of design compromises to choose between in this part of the camera alone. Since making the lenses interchangeable would increase complexity, size, and expense, that's generally not on the table — although the Nikon 1 and Pentax Q systems are challenging that (as are, to a lesser extent, the mirrorless cameras of the last few years). With interchangeable lenses not an option, that generally means the market demands zoom, and a compact zoom already means a lot of possibilities are given up.

And then there's the sensor, the other most important part of the camera. And features — image stabilization, viewfinder, LCD screen, controls. A camera company could decide to make all of these things awesome, but the cost would be astronomical.

The link you gave is to a class of camera with even further constraints: these are ultra-zooms with GPS. That means a certain size and form factor, and competition is going to be over the amount of zoom and features related to that (including, probably, ruggedness, since the GPS implies travel). And this market niche seems to have a price point of around $300; going over that would require something really special versus the competition, and if that specialness is not easily visible on the features summary at Big Box Electronics Store, consumers are going to balk.

There's a huge market for cameras, though, so if you're really interested in quality over price (and generally, over ultra-zoom), there's a re-emerging class of high-end compacts, including the Fujfilm X10 (not to be confused with the X100), the Canon S95/S100, and Olympus XZ-1. And in the last few months, camera companies released a couple of interchangeable-lens systems which compromise on sensor size in exchange for size — Nikon 1 and Pentax Q. These are priced in a way which has made many armchair industry observers blink. And, while deciding to use a small sensor, they're choosing other compromises other than cheap and betting that there's enough people interested that it'll work.