John Kerr, 51, registered as a county co-ordinator with the charity in 2011 to help raise funds.
He had an agreement with the Quarter Gill pub, in Dumbarton Road, that he would exchange coins donated in charity tins for notes, because it made it easier for him to bank.
But suspicions were aroused when Kerr was living beyond his means and some of the notes given to him by the staff to be banked were marked and seen coming back over the bar.
The charity and police were later contacted and Kerr was questioned and claimed he had no money from the charity.
But the day after being interviewed he took more than £5000 to the bank and told Help for Heroes it was a year's worth of Asda donations.
After a trial at Glasgow Sheriff Court, Kerr, from Scotstoun, Glasgow was convicted by sheriff Gillian Bryson of embezzling £6910 from Help for Heroes charity between February and December 2012.
Kerr was given a community payback order with the condition that he must carry out 260 hours work in six months.
Sheriff Bryson also imposed a compensation order for £1815, the outstanding balance that Kerr owes the charity which he will repay at £25 a week.
Help for Heroes carried out its own investigations and no traces could be found of any donations made by Kerr after events registered to the charity by him.
The charity notified the police who then interviewed Kerr.
His explanation for using the notes given to him by the pub was that he didn't like "dirty money".
He claimed he would swap his dirty notes for clean notes, that he got from the pub, but replaced them again.