I think you're forgetting about the fact that people grow old and stop doing this, and therefore no longer have any social pressure on them to not speak ill of

I think you're forgetting about the fact that people grow old and stop doing this, and therefore no longer have any social pressure on them to not speak ill of the idea? These parties have (presumably) been going on for a long time. If people wanted to speak out against them, then there'd be 50-year-olds writing angry screeds to "warn the youth of today" about "the mistakes they made in their own youth, and deeply regretted, but couldn't speak out at the time." But we don't see that.