Business caters to profit, and unless there is a profit in selling same-sex wedding accouterments then you're not going to find them. It's not "heteronormative", it's just the market. They are free top make the products they desire and sell them, just like they found when they used LGBTQI+++-knowledgeable realtors. Do they really think the realtors give a shit or do they see a market they can corner? As for the rest, the second they say "privilege", I'm done reading.