The incident took place in the Aliganj area in Etah, 265 km from here.
Pujari, who the police described as a criminal, ordered an omelette for four of his friends. When they found there were no onions in it, the group became furious.
Egg vendor Deepu Kashyap told them he could not not afford to buy onions, which have become expensive over the past few weeks.
Pujari then whipped out a pistol and shot at the vendor.
The victim was rushed to a medical facility.Inspector General of Police (Agra) Ashutosh Pandey told IANS that the assailants were local criminals with many cases registered against them.
"A case under attempt to murder and extortion has been slapped on them and we are trying to arrest them," the police official said.