It has been argued for decades that capitalism is the most legitimate system. And it is true that the majority of countries have transitioned to capitalism sooner or later. The concept is that the market itself determines the best prices for goods and balances them so that everyone is happy. There is no need for government intervention or a planned economy (which is not working at all); the laws of supply and demand regulate everything. Reality, however, tells us that this is not how it works at all.
The first problem encountered is monopoly. Simply put, if a firm acquires a monopoly position and virtually eliminates all competition, that firm can determine prices as it sees fit. Indeed, one could argue that other firms might appear that sell at a lower price. However, the monopolist is usually in a position to nip potential competition in the bud. In this country, a typical example would be cell phone service providers. It is no coincidence that for decades there have been only three providers.
Then there is the fact that there are things that people simply must buy, no matter what the price. For example, basic groceries and other necessities that we cannot do without. Even then, companies can basically drive up the price. When this is coupled with the aforementioned monopolies, it is a path to disaster.
Then there is the fact that people as a whole are susceptible and companies know this very well. Therefore, there is nothing wrong with making people think that they are better off paying more money and that there is an added bonus. This is often done in clothing stores, where clothing stores can afford to make a profit even with substantial discounts.
Thus, it is clear that capitalism is far from a perfect system and cannot exist without regulation. Nevertheless, for the time being, capitalism is the best we can hope for.