We say in the tefillah of Nishmas, "Even if our mouths were filled with praise like the ocean and our tongues were full of song like its multitude of waves... we would still not be able to properly thank you for even one of the millions and trillions of acts of kindness that You have performed for us." Rav Wolbe (Daas Shlomo) notes that Chazal's perception with regard to a person's obligation to give thanks to Hashem is astounding. Accordingly, one would have to be on the spiritual level of Dovid Hamelech to properly say thank you for a single bite of food!
In a similar vein Chazal tell us (Ta'anis 6b) that when the first rain of the season falls, one should bless Hashem and thank Him for "each and every drop of rain." A single rainfall, comprised of billions of drops, warrants billions of expressions of gratitude. Additionally, Chazal assert, "For each and every breath a person breathes he should praise Hashem" (Yalkut Tehillim 150). Analogously, while we perceive an orchard merely as a large group of trees, Chazal looked at an orchard as thousands of trees, each with tens of branches, thousands of leaves and hundreds of fruits. They appreciated each tree, branch and fruit as a gift from Hashem and they acted accordingly: They paid tribute for each drop of rain, they expressed their gratitude for each breath, and they blessed Hashem for every k'zayis that they ate.
Hashem could have designed the world in a way that people would not need to breathe more than once a day or eat more than once a year. Yet, He specifically created it in a manner that requires one to breathe numerous times every minute and eat several times a day. A world wherein one is constantly receiving new life and Heaven sent bounty, makes it easier for the recipients of such beneficence to acknowledge that every minute of their life is dependent solely on the will and kindness of the Creator.
How can it be, wonders Rav Wolbe, that despite the infinite acts of kindness that Hashem performs for us on a daily basis, not only do we not feel an enormous debt of gratitude, we still ask Hashem at any given opportunity to shower us with even more kindness? Such behavior seems to stand diametrically opposed to the conduct of Chazal where they felt obligated by each breath and every droplet of water!
The Mishna in Avos (5:22) enlightens us to the root of the issue. "Those who have a good eye, humble spirit and meek soul are among the disciples of Avraham Avinu, while those who have an evil eye, greedy spirit and arrogant soul are among the disciples of the wicked Bilam." What is the difference between a humble spirit and a greedy spirit? Bilam, as he expressed to Balak, felt that he deserved a "houseful of gold and silver." He wished to amass as much as the world could offer. In contrast, Avraham's attitude was similar to one who is impoverished and meek and rejoices even in the smallest things. It was this trait of appreciating every single solitary aspect of creation that led to his discovery of the Creator at age three and ultimately to him being picked to be the father of the Chosen Nation.
It all boils down to our outlook on the world. Is the world all about glitter and glamour with the aim to stuff our pockets with whatever we can? Or is the world made up of an infinite amount of gifts from Heaven above? If the goal is to fill our pockets, there is no reason to thank anybody for anything since we are simply doing what we are supposed to do. In contrast, if we perceive every sparkling raindrop as a diamond and every breath as a Divine gift, we won't stop thanking Hashem for His unending kindness. Indeed, big people appreciate little things.