Acting Rotorua area commander Inspector Ed van den Broek said some possible suspects had been identified but the YouTube video was a very useful addition to the investigation.
"Good solid police work had helped identify the alleged offenders, but the clip provided us with some visuals allowing us to confirm this work," he said.
"We don't know who was responsible for the clip and whether they were associated with the offenders, but it has certainly been helpful.
"What has been especially pleasing is the number of people who have forwarded the clip to police via our Twitter and Facebook accounts. Many thought and hoped that we were investigating the incident, but they wanted to make sure we knew.
"This is fantastic because it means people are taking an active interest in the safety of their communities, and sharing information with us that they think is important.
"Social media provide a forum for them to be able to easily do that."
The Daily Post newspaper said the video was filmed by a Rotorua man sitting in a vehicle outside Countdown Rotorua.
Progressive Enterprises national communications and public affairs manager Luke Schepen said earlier that the altercation took place about 10.30pm on January 4 and was a "distressing incident for our team members and our customers."
He added: "It is extremely disappointing that these types of incidents do occur."
