The first generation of FatLanders were so pleased to be able to live their lives without stigma and without persecution that they weren't interested in rocking the boat socially. They were pleased and often thrilled to be appreciated and admired. They were tickled to be able to marry, to work, to mingle, to have social lives, to walk up and down streets without being jeered and harassed.
The second generation, however, born and raised in FatLand, took their freedom/s from stigma, persecution and harassment for granted. (This was, however, at least partly because their parents could not bring themselves to speak of the horrors of the Pro-Health and Diet administration and years.) Many started to rebel against what they perceived as the stolidity and boring nature of life in FatLand.
However, the ones who were either sent to the OtherSide/USA or heard or read in more detail about the Pro-Health and Diet times started to appreciate anew life in FatLand.
But it was true that the second generation was not as interested in marrying (one person at a time) or setting up cozy, nuclear style families.