Street robbers often carry out their crimes for the thrill as much as for the financial gain, a report has said.
The motives behind muggings are poorly understood, the report says
The Economic and Social Research Council (ESRC) study interviewed 120 offenders in England and Wales.
The report said previous attempts to explain violent street crime put too much focus on the desire for gain, and not enough on the aspect of "pleasure".
The study comes a day after the fiancee of murdered lawyer Tom ap Rhys Pryce criticised his killers' "bravado".
In a statement read to the Old Bailey, Adele Eastman said Donnel Carty, 19, and Delano Brown, 18, who were convicted of his knife murder, had been "trying to play the big man".
Meanwhile, Mr ap Rhys Price's father has set up a charity to help divert young people away from street crime.
John ap Rhys Pryce told BBC Radio 4's Today programme that young people could release their energies without being violent.
"I can understand it, in a way. But I think that we have to try and divert that desire for excitement or kicks or buzz, whatever you like to call it, into a different direction."
He added: "The idea is to try to help people who are in a disadvantaged situation... to get educational facilities."
He said this "could mean sport or music as well as ordinary academic help so that they can achieve their potential... rather than just wandering the streets".
The report by Professor Trevor Bennett, director of the University of Glamorgan's Centre for Criminology, and Dr Fiona Brookman, said both the amount and the severity of gratuitous violence used in street robbery was increasing in the UK.
It was a "worrying social problem" that was poorly documented and understood, it said.
Some offenders found robbery to be a pleasurable activity in itself, interviewers found.
"It weren't even for money. I had money. It was more like the buzz you get from doing things," one interviewee told them.
The report's authors said part of the excitement for offenders came from overpowering and dominating the victim.
"Anger and the desire to start a fight" was another motivation.
Cash made from crime was often spent on "status-enhancing" items to boost the offender's street credibility.
"After we done a few armed robberies, I bought a brand new car. It's like showing off, really," said one interviewee.
The study interviewed 89 males and 31 females, of whom 36% had been arrested more than 50 times, 17% between 25 and 49 times, and 30% between 10 and 24 times.
The average age of the offenders interviewed was 26, and a third of them said they belonged to criminal gangs.
Some 28% said they carried guns and another 35% said they carried some other weapon, usually a knife.
Prof Bennett said: "The decision to commit street robbery can be explained in part by particular characteristics of the street culture.
"This finding is important, because British research has tended to explain robbery in terms of rational choice and to focus instead on the role of cost-reward calculations."
Just for 'kicks'?
Camilla Batmanghelidjh, founder of the charity Kids Company, said street crime was a "systemic problem".
She said: "It would be really sad if this report got translated as a bunch of young people robbing for fun. It is not about that.
"It is for 'kicks', but you've have to understand what the 'kick' is. The 'kick' is people who are victims for prolonged periods of time developing a cycle of revenge so that they then get a high from victimising someone else."
Chris Stanley, from the crime reduction charity Nacro, said that the offenders questioned for the survey had a background of multiple serious offences.
"This research should not send a wave of fear through society," he said.
"The people interviewed have a background of multiple serious offences and should not be seen as a typical sample of those committing robbery.
"The research does highlight the fact that the causes of robbery are complicated, and doing it 'for kicks' is just one element, along with desire for gain, often linked to drugs, and the escalation of bullying."
The Economic and Social Research Council, which conducted the study, is an independent body which funds research and training in social and economic issues.