wouldn’t a housewarming party be a socially acceptable way for a single person to create a registry?
as a Married Person who attends weddings, i get these posts, but also kinda shrug at them because it feels like hyperbole to describe wedding attendance and gifts as “obligations.” i know some people are not so chill, but i had very few expectations of my guests. i held the wedding in the city where i live, but many of my family and friends live elsewhere, and i did not expect or pressure anyone to come. nor did i get miffed about not receiving a gift in any circumstance. i know people have lots of demands on their time and budgets, and i was truly grateful when they chose to share their time and budgets with me. my maid of honor is a broke graduate student, so my family and i paid for the bridal shower, her dress and hair and makeup, and also gave her a lovely necklace as a gift for her work coordinating everything.
if the bride and groom aren’t pressuring you to come to the pre-wedding festivities, the wedding itself, or bring a gift, then the idea that it is an obligation is kinda in your head. and if they are pressuring you, well, they’re dicks, so no harm no foul.