Hello Aaron,
Thanks for the question about having your blog navigation only appear on blog pages and then having your shop navigation appear on your shop pages. The only way I can think of that happening with the native functionality within BoldGrid or WordPress is to have landing pages for the Blog site, the Shop, and a home page with links to both. You would have to create specific menus for each landing page that includes only the navigation for the sections you mentioned. Other than that, you would need to have a plugin where you can manage the different items of your menus. I hope that helps!
If you have any further questions or comments, please let us know.
Regards,
Arnel C.