Declaring WooCommerce support in child theme- help

My website is not currently live, it is hiding behind a landing page while we work on it.

I have added the woocommerce plugin and used the information here (https://github.com/woocommerce/woocommerce/wiki/Declaring-WooCommerce-support-in-themes) in order to override template files in my child theme.

The one thing at the moment I want to change is to remove the sidebar on single product pages. I was able to do that without any problems..

However, on the /shop page, the footer has extended upwards and covers nearly the entire page.

I removed the overriding template and there was no change. When I removed the extra code in functions.php declaring woocommerce support, then the footer returns to normal. This only affects the footer on the /shop page.

There appeared to be a secondary issue as well where links to listings (WP Job Manager plugin) led to 404 pages. When I removed the code from functions.php the links functioned properly. However, I have added the code again and the links are working normally, so this might be an unrelated issue.

So my main concern, is why does declaring woocommerce support in functions.php affect the /shop page immediately?