International retail marketing company TCC handles such licensing for Rovio, the creator of the wildly successful game under an agreement signed earlier this year.
Henri Holm, senior vice-president of Rovio Asia, said that Wellcome is a natural fit for Angry Birds to migrate from digital to retail.
The promotion gives shoppers the opportunity to collect stamps for each purchase over the next 13 weeks. The stamps can then be exchanged for one of eight Angry Birds plush toys.
Wellcome is the first Hong Kong retailer to license the Rovio characters in this way. TCC has done similar partnerships with Carrefour, 7-Eleven and City Cafes in Taiwan, as well as 7-Eleven in Singapore.
Angry Birds-themed promotions have delivered an average sales increase of 21.7 per cent, far exceeding the typical lift of between 3 and 5 per cent, according to Simon Hall, TCC's regional business development director.
The multi-year agreement from Rovio grants TCC worldwide rights in a wide range of retail distribution channels including: supermarkets and hypermarkets, drug stores, health and beauty chains, newspaper and newspaper kiosks, fuel chains and convenience stores. TCC and Rovio have developed products include a range of figural ceramic mugs, pens, soft toys, balls and luggage.
Apart from this retail partnership, Rovio opened a Shanghai office and a retail location on 3 July, the first outside of Finland. Beijing will get a similar store on 10 July.
According to local media in China, Shanghai Tongji University is going to host China's first Angry Birds Activity Park, which will be established in the university's Sino-Finnish Center around October this year, featuring rides inspired by the game.