Thanya (real name withheld) who first started smoking four years ago, also said plain packs would not be a deterrent.
Plain-packaging will usually deter young people and first-time smokers, said Bungon Ritthiphakdee, from the Southeast Asian Tobacco Control Alliance.
However, this is one strategy among several to reduce tobacco consumption and must be implemented in parallel with other deterrents, such as price rises, she said.
"Still, since tobacco companies oppose plain packs so much, it must mean they are working.