Why should any of life’s essentials ever need to be subsidized in a free market capitalistic society?

In a free market capitalistic society that's in equilibrium for many generations, everyone has housing, food, healthcare, water, clothes, etc. This society has evolved in a way to sustainably produce these things in such a way that the people feel confident to start families and hence, don't have scarcity in mind.

However, suppose that in this society, the farmers can't sell their produce at a profit. Is this a good thing? It means that the food prices, relative to other products and services, is inexpensive. This scenario, for the general public, is better than having too little food that's priced too high. The farmers can't get a good wage for their work, so in my opinion, this society has too many farmers who should consider a new vocation.

In our society in the USA, we subsidize farmers (probably for republican votes), but this tells me that we're taxing some industry to subsidize farmers, but this leads to much in inefficiency because it costs money to administer this bureaucracy, and there are losses associated with this re-allocation.

How is it possible in a steady-state society that an essential product or service requires subsidization? Subsidizing an industry for essential items indicate to me that this society is now unsustainable. Also, some other parts of this society is either too profitable and able to generate a lot of profit, which is then shared in the form of subsidies. But profitable sector that's generating profits is also not sustainable, because it implies that there's a shortage of this product or service.