At the place I worked that skipped FK checks, they used append-only database schemata. If you limit yourself to CR operations, a lot of things get easier than t

At the place I worked that skipped FK checks, they used append-only database schemata. If you limit yourself to CR operations, a lot of things get easier than they are with CRUD - ensuring (a somewhat weak form of) database consistency without transactions, yeah, but also things like audit trails and slurping new data into the BI system.