An overarching theme of most of John Steinbeck's literature, not just Tortilla Flat, is the intrinsic yet underestimated beauty and goodness of simple things. This is the reason why Steinbeck chooses the paisano of Monterey as the topic of the book. They are not cultured or worldly people, but in their ignorance of modern technologies and ways of thinking, there is something enigmatic and appealing about them. They are truly free in ways that societal influences prevent other people from being.
The Pirate is another example of how a simple thing, in this case a mind, is shown to be far from worthless. He is a huge man with the mind of a child, and when Danny's friends catch on to the fact that he is hoarding money, he is defenseless against their manipulations. He is saved however by the simple innocence and sincerity of his intentions for the money, and also by the fact that he is ignorant to what the friends, led by Pilon, were doing to him. Instead of leading the friends to the money so that they could eventually take it, he comes out and simply gives the money to them, thinking that it would be safer with them. When they see this and hear the conviction in his story about San Francisco and the sick dog, the friends completely reverse their purposes. They help him to reach his goal of a thousand quarters and the money becomes a physical representation of their friendship.
Steinbeck supports the theme of simplicity by introducing modern conveniences into Tortilla Flat and showing what problems they become. The vacuum cleaner that Danny gives to Sweats Ramirez is a perfect example of this. She likes it because it is sleek and shiny, even though it has no usefulness whatsoever. When the vacuum is later traded to Torrelli, a scandal is created by the fact that it has no motor, symbolizing the emptiness of conveniences like the vacuum. Similarly, the friends come across a machine gun in the flotsam from a downed coastguard ship. Whereas Danny is very business savvy in everything else, he has no idea of the use and value of such an object and so he sells it at a low price with the rest of the junk that they find.
Steinbeck spends a lot of time during the adventures of the paisano describing the landscape around them. This is not just a story about a group of friends; it is also about a community. Because Monterey plays such a large part in the characters of Danny and his friends, Steinbeck must give the town life and color so we can understand them better. Though they are not characters in the book, Steinbeck constantly refers to how the fisherman who believe that fish bite more in the morning were replaced by those who think they bite more in the afternoon, and then dusk, and then night. There is the tailor who puts the, "Back in ten minutes," sign in his window no matter how long he was going to be gone for, the drunkards in the ditches, and the houses of ill-repute with their girls hanging out the window. All of these seemingly needless details help us understand the way of life in Monterey, which can then be applied to Danny and his friends.
There is also the fact that Monterey is one of the most ruggedly beautiful pieces of landscape in all of America. It's character, with its lazy hills, warm sun, spectacular shoreline, and colorful plant and animal life closely matches the paisanos themselves. Often Danny and his friends spend entire days just staring at it and enjoying its splendor. Pilon, in particular, is often halted in his tracks by the almost spiritual beauty of the place. It is also worth noting that the weather in Monterey coincidentally aligns itself with the spirits of the characters in many places. When all the bonding and adventuring is going on, it is warm, sunny, and pleasant, but when Danny begins feeling down, it is nothing but gray.
Though one might expect characters like the paisano to be jaded in their spiritual beliefs by the freedoms of their lifestyle, this is not true of the inhabitants of Tortilla Flat. They are an extremely God fearing and reverential people. They are strong believers in miracles and guidance from above. Whenever there is a little extra money (not enough to buy wine or food with) it is spent on candles to be burned for San Francisco or other saints. The myth of St. Andrew's Eve is not something that a few superstitious children believe in; it is a town wide event.