Every single law and practice that either excludes LGBT people or discriminates against them directly contributes to a culture in which homophobia is the accepted norm. Children in gay- and lesbian-headed households also suffer from this societal attitude. They often suffer ridicule or exclusion just because of the sexual orientation of their parents.
With more and more states offering marriage equality, with antidiscrimination laws being enacted, with the repeal of Don’t Ask, Don’t Tell, and so on, clearly the legal problems that the community face are easing — although not fast enough. And the societal homophobia is falling right along with it.