Hi,
There is no way to deactivate this using the UI, but you can customize the template in your own theme.
For example, if you are using the skin #2 and the WP theme twentytwnetyone you can run the following
cd [path-to-your-wordpress-folder]/wp-content/themes/twentytwentyone/
mkdir wpsc-views
cd wpsc-views/
cp ../../../plugins/wp-smart-contracts/skins/wpsc-theme-light-2/wpsc-views/nft-view-menu.mustache .
Then, using a text editor open the file:
wp-content/themes/twentytwentyone/wpsc-views/nft-view-menu.mustache
and remove the following block:
<div class="the-tag yellow-tag right-aligned black-color">
<a href="{{mint-link}}">
<span class="tag-main-text">Mint a new Item</span>
</a>
</div>
That should do the trick