The Gemara on Amud Beis tells us that the Cohanim actually are beneficiaries of the very same blessings they pronounce.

אָמַר רַבִּי יְהוֹשֻׁעַ בֶּן לֵוִי מִנַּיִן שֶׁהַקָּדוֹשׁ בָּרוּךְ הוּא מִתְאַוֶּה לְבִרְכַּת כֹּהֲנִים שֶׁנֶּאֱמַר וְשָׂמוּ אֶת שְׁמִי עַל בְּנֵי יִשְׂרָאֵל וַאֲנִי אֲבָרְכֵם וְאָמַר רַבִּי יְהוֹשֻׁעַ בֶּן לֵוִי כׇּל כֹּהֵן שֶׁמְּבָרֵךְ מִתְבָּרֵךְ וְשֶׁאֵינוֹ מְבָרֵךְ אֵין מִתְבָּרֵךְ שֶׁנֶּאֱמַר וַאֲבָרְכָה מְבָרְכֶיךָ

Rabbi Yehoshua ben Levi says: From where is it derived that the Holy One, Blessed be He, desires the Priestly Benediction? As it is stated: “So shall they put My name upon the children of Israel, and I will bless them” (Numbers 6:27). This shows that God waits for the priests to bless the people, and only then He Himself blesses them. And Rabbi Yehoshua ben Levi says: Any priest who blesses the people is blessed from Heaven, and one who does not bless the people is not blessed, as it is stated: “And I will bless those who bless you” (Genesis 12:3).

Pele Yoetz (22, “Berachos”) applies this idea to all Berachos that we recite over food, and other important events: Whomever recites blessings will be blessed, and whoever does not, causes curses to be brought upon himself.

The Kuzari (3:16-17) says a modern sounding idea about Berachos and mindfulness. Part of why Hashem wants us to make blessings is to enhance our enjoyment through mindfulness. Kuzari observes, “If a drunken person were given all he desires, whilst being completely intoxicated, he would eat and drink, hear songs, meet his friends, and embrace his beloved. But if told of it when sober, he would regret it and regard it as a loss rather than a gain, since he had all these enjoyments whilst he was incapable of remembering and appreciating them…Preparing for a pleasure, experiencing it and looking forward to it, doubles the feeling of enjoyment. This is the advantage of the blessings for he who says them with attention and devotion. They produce in his soul a kind of pleasure and gratitude towards the giver. He was prepared to give them up; now his pleasure is all the greater, and he says: 'He has kept us alive and preserved us.' He was prepared for death, now he feels gratitude for life, and regards it as gain.”