No states legally recognized same-sex marriage before 1996. Same-sex marriage was a relatively new controversy at the time, but one major reason for that was because Republicans were able to use the issue to motivate their base by trying to preemptively curtail it. Furthermore, DOMA was passed with a broad enough majority that any veto would have been overridden anyway. Picking a fight on DOMA would have only further motivated efforts at the time to prohibit same-sex marriage with an amendment to the US Constitution.

The 1993 ruling in Baehr v. Lewin simply remanded the case to a different count; it did not "find bans on GLB marriage unconstitutional". In fact, by the time the final ruling happened (as Baehr v. Miike), the Hawaii constitution had been amended anyway.