Health: By buying these products -“Pride” – (hopefully they are clearly labeled as such -so other products in Target are Muttar;)
you are directly being Meesiyah Leiday Aveira!
Toeiva isn’t illegal in the US. Giving money to these groups can only possibly change some marriage laws, not laws about personal preference. Whether you give these groups money or not, no one can stop the Ta’avtanim from committing their aveiros.
I personally, prefer not patronizing stores that support the advancement of Toeiva ideology. A Hashkafic decision, but not Halachic.