“Butterflies raised by unregulated commercial interests may spread diseases and parasites to wild populations, with devastating results. Often, butterflies are released great distances from their points of origin, resulting in inappropriate genetic mixing of different populations when the same species is locally present. When it is not, a non-native species is being introduced in the area of release. At best, this confuses studies of butterfly distribution and migration; at worst, it may result in deleterious changes to the local ecology.”
https://baynature.org/2019/07/23/butterflies-are-more-than-party-favors/