gistfile1.php

<?php

add_filter( 'tribe_events_filter_values', 'tribe_filter_event_categories', 10, 2 );
function tribe_filter_event_categories( $values, $slug ) {
	if ( $slug == 'eventcategory' ) {
		foreach ( $values as $i => $category ) {
			if ( $category['name'] == 'Event Category 1' ) {
				unset ( $values[$i] );
				break;
			}
		}
	}

	return $values;
}