There's a pretty clear hierarchy within a caucus and within a cabinet. Put Morneau as the Minister of Sport and see how he likes it. Prime Ministers have long used their power to appoint and remove MPs to/from different cabinet posts, committees, and schedule speaking time in the House of Commons etc. to reward or punish MPs based on their obedience. Parliament is one big ass-kissing party.
Sure but Trudeau made a pretty big show of making all Ministers equal within his government.