The Mad Hanar wrote...
Just imagine if McDonalds was a mom and pop burger shop. They sell the best burgers and coldest sodas in town for cheap. They have a small, loyal and sustainable consumer base and the production costs are as low as the prices. Suddenly, they blow up. More and more people come into the store, which drives production costs up since they have to make more. On top of that, Burger King uses a better, but more expensive, cheese. In order to compete with them, they have to buy that cheese which drives production costs up more. Since this is happening, the profits for the chain gets thinner and thinner. So they decide to tack on fries for an extra fee. This works for a while, but then people start calling them greedy, as they feel fries should be included with the original meal. So at this point Mikey D's has three options, keep a good reputation and eventually lose their profit, keep their fries model and gain a bad reputation and stay sustainable or increase the base price of the meal while including the fries and gain a bad reputation and go back to the profits of their mom and pop days.
If McDonalds put out a consistently good product, and had a less dramatic price increase, people may be more willing to accept the necessity to maintain that level of quality.
However, if "McDonald's'" were to, say, over the last several years, seriously drop in quality, greatly increase the cost of their drinks wile adding extra salt to their fries, and most recently try to serve rancid burgers, then claim that raising their prices by a third was necessary to maintain this level of quality, yeah I'd be skeptical of their motives