Sami Hamdach, 30, had pleaded guilty to the murder of Ross Houllis, 28, who died in hospital three days after he was bashed on a suburban Wakeley street in Sydney's west on Valentine's Day 2020.
Justice Stephen Campbell sentenced Hamdach to a total of 16 years and two months with a non-parole period of 12 years in the NSW Supreme Court on Friday.
Outside court, Mr Houllis' mother, Janet Houllis, reacted after learning the sentence given to the first of two men to be jailed over her son's death.
"I would have been happy with longer but it is what it is," she told reporters, holding a framed photograph of her son.
"It's not going to ever bring him back."
Hamdach bought a pair of purported Apple AirPods from Mr Houllis the day before the attack and believed they were not genuine.
His partner arranged for Mr Houllis to meet and sell another pair, when he was ambushed by Hamdach and another man, Abdul Karaali.
"(Hamdach) could have done a lot of things to stop it," Ms Houllis said.
"Yes, I mean, the other guy was aggressive ... (Hamdach) had 24 hours to stop it."
He planned to demand a refund and teach Mr Houllis a lesson by beating him up, enlisting Karaali as "muscle", Justice Campbell said.
The motivation behind the plan that led to Mr Houllis' death in the prime of his life, a non-genuine version of a popular consumer product, was "trivial".
"A flagrant example of the offender taking the law into his own hands, which can never be tolerated, let alone condoned," the judge said.
CCTV captured the scene as Mr Houllis was set upon in a shopping centre car park, "frogmarched" towards his home, kicked in the head in a suburban street and stomped on.
Passing motorists who stopped to check on Mr Houllis' welfare were told he was intoxicated and his two killers were looking after him.
Hamdach "left Mr Houllis for dead effectively" when the pair left the scene, Justice Campbell said.
Karaali was found guilty by a jury earlier in March and faces a sentence hearing in July.
"He is the primary offender responsible for the death of Mr Houllis," the judge said.
He highlighted the "gratuitous, senseless and cruel manner" in which Karaali stomped on an already concussed Mr Houllis.
Hamdach's partner previously received a two-year intensive corrections order for being an accessory before the fact to assault occasioning actual bodily harm.
Justice Campbell noted Hamdach had "no real criminal record" before the murder, and it was "confounding" Mr Houllis died over "such a trifling matter".
"I do not pretend to have found the answer to that question," he said.
Exposure to violence and aggression from a young age from his father who would readily dole out "fatigue-type punishments" he learned in the Lebanese military, might explain Hamdach resorting to violence over a minor conflict, the judge said.
He was also persuaded Hamdach was suffering from a schizoaffective disorder involving mania, exacerbated by drug use.
Hamdach read a letter of apology to the Houllis family at his sentence hearing and the judge accepted he was sincerely remorseful.
"It means nothing to me," Ms Houllis said outside court.
Hamdach has been in custody since his arrest the day after Mr Houllis was ambushed, and will be first eligible for parole on February 14, 2032.
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