Originally posted by biz-engineer Of course, all cameras are reviewed and sold based on "needs" that are completely made up (the race for bigger numbers in spec sheets and spec sheet comparisons, the high the better even if practically never used), and unrelated to unbiased real world usage. If cameras were designed purely on real world usage, we would have the choice between [1] 4K (8 megapixels.. yes) cameras, all with slow motion video capability and seamless high speed wireless connectivity and [2] 100Mpixels medium format cameras at 1 frame per second purely for high quality stills, with both type of cameras being priced fairly close.
I think you're dramatically over-simplifying things. An 8 Mp camera would be really fast, but allow very little, if any, overhead for cropping. People want cameras that do a range of things. My 24Mp APS-C camera is pretty darned good for landscape, it's okay for sports, it's good for macro, and probably not so bad for portraits if I did that type of thing. I can pop a 15mm or 21mm LTD on it and take great travel photos. I can put a 55-300 PLM on it and take thousands of pictures of my kids' soccer teams. Much of that wouldn't be nearly as good on an 8Mp camera, and most of that wouldn't work at all on a 1 fps MF camera.
The market has made 24-36 Mp cameras that do a lot of things well but nothing excellently for the same reason there are more cars available than an 18-wheeler and an F1 car. My Audi isn't nearly as fast as a race car, nor can it haul 1/100th as much as a Peterbilt, but it hauls what I need and is a lot of fun at a semi-reasonable price.
We're not all idiots, mindlessly buying things that are bad for their intended uses. We buy stuff that compromises in ways that work pretty well for what we want to do.