Kansa means identification of oneself as the body. When we allocate time to perform activities such as eating food, sleeping etc to sustain this body, we are effectively appeasing this body identification by paying our dues to it.
Meanwhile, back at Gokul (meaning our collective senses), these cowherds were allured by Putanāʼs attractive outward appearance and let her in rather than be cautious. At that time if the Demi-Gods guarding our senses open the doors of our ears, eyes, tongue, etc to receive the pleasure of the senses upon sighting the beauty of Putanā, we place our inner bliss (Shri Krishna) at risk.
This is beautifully described by Tulsidāsji in Uttarkānd of Ram Charit Manas as the windows of our senses being thrown open to receive the gust of sensory pleasures.
Pujya Bhaishri explained that the gaze of the Lord contains knowledge of That Highest Reality and the Lord does not grant this to all. These and many others are reasons why our Acharyas have stated Shri Krishna closed His eyes at the time of liberating Putanā.