Okay I figured it out. I trimmed off the subcategories, but my problem was that I was not associating category with the field and value. So the $cat was acting as the post id in the same way that a page will render an ACF value.
<?php
$taxonomy = 'product_cat';
$orderby = 'name';
$show_count = 0; // 1 for yes, 0 for no
$pad_counts = 0; // 1 for yes, 0 for no
$hierarchical = 1; // 1 for yes, 0 for no
$title = '';
$empty = 0;
$post_id = 1;
$args = array(
'taxonomy' => $taxonomy,
'orderby' => $orderby,
'show_count' => $show_count,
'pad_counts' => $pad_counts,
'hierarchical' => $hierarchical,
'title_li' => $title,
'hide_empty' => $empty,
);
$all_categories = get_categories( $args );
foreach ($all_categories as $cat) {
if($cat->category_parent == 0) {
$category_id = $cat->term_id;
$icon = get_field('category_icon', $cat);
echo '<div class="cat-box"><a href="'. get_term_link($cat->slug, 'product_cat') .'">'. $cat->name;
echo '<div class="clear"></div>'. $icon;
echo '</a></div>';
}
}
?>
