RSA Otago Southland district president Jenepher Glover said the taggers reponsible for the George St graffiti showed a lack of respect.
Defacing the large posters in such a prominent location was "extremely hurtful to veterans and their families'', Ms Glover said.
She believed the culprits must have been ignorant of the significance of the Poppy Appeal and that it raised money for soldiers who fought for their freedom.
"I'm sure they wouldn't have done it otherwise.''
Inside Out Clothing owner-operator Cindy King said she noticed the damage to the posters opposite her shop yesterday morning.
It was "terrible'' they had been ruined less than a week after they were put up by Phantom Billstickers.
"Not only is it so disrespectful to the city, it's disrespectful to Anzacs,'' Ms King said.
Phantom Billstickers regional operations manager Amber Sharma said one of the culprits was believed to be a prolific tagger who went by the "handle'' Twiks.
Some of the other tags on the posters could be done by a different tagger, but company staff could not decipher the handle, Ms Sharma said.
There had been an "influx'' of graffiti in recent times and Twiks was among the most prolific.
Staff checked sites daily and removed graffiti.
The Poppy Appeal posters were replaced yesterday.
Phantom Billstickers is working with the council and Keep Dunedin Beautiful to stamp out graffiti.
Images of the graffiti were being collected and linked to different taggers.
Cr David Benson-Pope, who has been an advocate for tackling Dunedin's graffiti, called on people to report tags to the Dunedin City Council as soon as they saw them.
"The more people who feel this is an issue and the faster they report it to DCC, the faster we get on top of it and it gets fixed.''
