pg_anon_dump script should reset sequence tables
We've found that when importing data generated from this script the sequence data is lost. The dump file does not generate commands such as:
SELECT pg_catalog.setval('public.tablename_user_id_seq', 500, true);
I'm not sure if this is the cleanest approach, but I've updated your script to included the commands taken from the bottom of this page for resetting this sequence data: