An eyewitness exclusively told RadarOnline.com the reality star “was ordering spiked lemonade" with a male friend at a stand at the Prudential Center in Newark, New Jersey on August 26.
They also carried two glasses of red wine.
Though Ronnie, 33, and his pal were alone at the bar, the star was getting frustrated with fans taking photos of him.
"He was getting annoyed, and he was constantly on his phone," the eyewitness said.
The onlooker said he downed at least five drinks while hanging out in the concourse area, and hopped around to two different bars.
Ronnie’s drinking comes one week after he was shown checking into rehab on the latest episode of Jersey Shore: Family Vacation.
Radar readers know the star admitted to entering treatment after his partying and relationship spun out of control.
“I was just making the wrong decisions and I was very depressed. When I was depressed, I would turn to drinking,” the dad of Ariana, 1, told Us Weekly in February. “When I would drink, bad things would just continue to happen because I wasn’t reacting the way I should.”
Despite once insisting he was committed to recovery, Ronnie seemed to have no interest in staying sober on Monday night.
According to Radar’s eyewitness, “he was looking for shots, too!"