Some people are judging the club friendly match thinking that is how the main competition will go which is not suppose to be view like that
For the fact that a club performed well in the club friendly does not give a guarantee that they will also do the same in their domestic league because several times I have seeing underdog teams wining those teams that we think they're more superior but when they return to thier domestic league their performance is not going to be like that of thier performance during friendly game so I just feel that most clubs don't value this friendly game as they value thier main league so viewing it this way is wrong.
You are right about what you just said concerning the friendly game. For me, I think putting too much seriousness into these friendly games seems to be too much work because by the time the league starts, some players may even be tired as a result of the friendly games.
During the friendly matches, players just take it as a game to exercise their bodies and prepare for the games that will take place during the season. Most big clubs don't even take the friendly games very seriously because they don't really count. The purpose of these friendly games is for preparation for the players and also for the coach to check if his tactics and formation are good for the team.