There's no reason features that don't add substantially to marginal cost of production shouldn't be included in cheaper products. Failing to put this there is just a way of crippling the cheaper products. In Canon's case, it seems to be a calculated move to prevent their low end products from cannibalizing sales from their flagships. Whether or not this will be a good business strategy for them is an empirical question -- but I would find it hard to recommend the rebel line to a serious user on a tight budget.
Let's look at this a different way. There's no reason features that don't add substantially to marginal cost of production shouldn't also be included in more expensive
products. So failing to include them is just a way of crippling the more expensive
products. And even if they do add a few pennies to the marginal cost, that extra cost is much more easily added to the more expensive product -- so why not add it?
For example, the 5DIII lacks the "Creative Filters" of the SL1. The creative filters offer a number of special effects: Toy Camera, Fisheye, Miniature, Grainy Black & White, Soft Focus, Art Bold, Water Painting and Miniature Movie. Not only that, but the 5DIII lacks special scene modes found on the much cheaper SL1, like Candlelight, Food, Kids, Night Portrait, HDR Backlight Control and Handheld Night Scene. See how the 5DIII is "crippled"!
Yikes, the 1DX is "crippled" too!
Based on some arguments in this thread, we might conclude that it would cost "nothing" to have included such features in the 5DIII. And yet the SL1 has them, and the 5DIII doesn't. So why the heck did Canon "cripple" the 5DIII by omitting so many features? Why doesn't the 5DIII have fabulous built-in creative filters like Toy Camera and Grainy Black & White? Is Canon just being greedy? Or are they just being foolish, losing potential customers to competing brands?
Of course, different users have different expectations. So the 5DIII is not actually "crippled" by the lack of those creative filters, because the buyer of a 5DIII is not likely to want them or use them -- although a few buyers might
. Many buyers might find such creative filters to be an annoyance on their advanced camera. But those few buyers who actually want Toy Camera, Grainy Black & White and other creative filters on their 5DIII can complain that it would cost "nothing" to add, and it would be of no consequence to add a "creative" tab to the 5DIII menus. Without it, they are "forced" to buy the SL1 or another camera that has such features.
So the argument works both ways. If basic cameras should have advanced features from advanced cameras, then advanced cameras should have basic features from basic cameras. That is, if you don't mind the added clutter
that many buyers would find annoying and useless, and which might drive them toward a competing product that is more rationally designed
to meet their