Investigators in Council Bluffs, Iowa, say Larry Ely Murillo-Moncada, 25, had apparently fallen into an 18-inch (45cm) gap at No Frills supermarket.
Noise from the coolers probably muffled his cries for help, according to investigator Sgt Brandon Danielson.
No foul play was detected and his death was ruled to be accidental.
His body was discovered in January at the store less than a mile from where he lived, but was so badly decomposed that he was not positively identified until last week after a post-mortem examination was conducted.
