WordPress get_posts() vs query_posts() MySQL behavior

gistfile1.php

<?php

/**
 * Am I missing something obvious?  Is there some flag for caching attachments or something?
 *
 * My actual use case is pulling all the posts from a custom post type... but the behavior is the same with good old plain posts, too.
 * Your test posts will need Featured Images.
 */

/**
 * Use one or the other PHP block in this gist... not both.
 * Place this in any theme template file between the get_header/get_footer
 */

$args = array(
    'post_type' => array('post'),
    'post_per_page' => -1,
    'posts_per_archive_page' => -1,
    'nopaging' => true
);

query_posts($args);

while (have_posts()) : the_post();

    // Number of MySQL queries is fixed, regardless of number of posts
    // (Measured with Debug Objects plugin)
	?>
	
	<p><?php the_post_thumbnail(); ?></p>
	
	<?php
endwhile;

wp_reset_query();

?>



<?php

/**
 * Use one or the other PHP block in this gist... not both.
 * Place this in any theme template file between the get_header/get_footer
 */

$args = array(
    'post_type' => 'post',
    'post_per_page' => -1,
    'posts_per_archive_page' => -1,
    'nopaging' => true
);

$posts = get_posts($args);

// Can do it this way too with same behavior
//$query = new WP_Query($args);
//$posts = $query->posts;

foreach ($posts as $post) {
    
    // get_the_post_thumbnail() here results in 3 MySQL queries PER POST!!
    // (Measured with Debug Objects plugin)
	?>
	
	<p><?= get_the_post_thumbnail($post->ID); ?></p>
	
	<?php
}

?>