He was initially charged with aggravated robbery, to which he entered no plea, and he sought to challenge the barman's identification of him.
After what sentencing Judge Gus Andree Wiltens described as "an arm wrestle" with the prosecution about what he should be charged with, Opetaia pleaded guilty to demanding property with menace - over a year after the offending.
A Court of Appeal decision, released today, said Opetaia had sought to have the sentence reduced on the grounds that the offending was a one-off, relatively opportunistic, ill-planned, and only a small amount of money was obtained.
His lawyer, Kathryn Maxwell, further submitted that while Opetaia had more than 70 previous convictions, including for serious offences involving violence, Judge Wiltens had failed to distinguish between his pre-1996 offending and his relatively minor offending over the last 13 years.
Ms Mawell also said that a further discount should have been allowed in light of Opetaia's efforts to disassociate himself from the Black Power gang and his desire to receive counselling.
He claimed to have strong support from his whole family, which includes 11 children by different mothers and 25 grandchildren.
However, the Court of Appeal judges agreed with Judge Wiltens that Opetaia was "at an age where one might have thought [his asserted wish to rehabilitate himself and again become a law abiding citizen] would have occurred a long time earlier".
Justices Lester Chisholm, Judith Potter and John Wild also found that a discount of 15 per cent for his guilty plea was appropriate, perhaps generous, given the late stage at which he entered the plea.
