I would remove them, but I no longer have access to your theme because the app is uninstalled. I will send a temporary admin request allowing me to remove the sections on your shop.
If you'd like to remove the section content yourself, delete all files in the snippets folder starting with 'sa-'. You can also delete any file starting with 'atb.' or 'atb-'.
We would remove sections upon uninstall, but 99 percent of the time shop owners want the content they've built to remain in tact.
Please let me know when or if you've accepted my temporary admin request and I will remove the sections.