Filter JetPack infinite scroll type based on template

functions.php

<?php

/**
 * Ensure that JetPack uses "click" for infinite scroll
 * on the front page, regardless of all other settings.
 *
 * We need to filter the JS settings because all other
 * means of controling scroll vs click are initiated
 * before the template conditionals know which page
 * we're viewing.
 *
 * @param  array $settings JetPack Infinite Scroll settings.
 * @return array           Modified settings.
 */
function rzen_infinite_scroll_js_settings( $settings = array() ) {
	if ( is_front_page() ) {
		$settings['type'] = 'click';
	}
	return $settings;
}
add_filter( 'infinite_scroll_js_settings', 'rzen_infinite_scroll_js_settings' );