Fishes and loaves? Didn't have to be done, as the crowd could have dispersed to find food.
The fact is that Jesus performed miracles as signs as well as miracles of healing.
I never said otherwise. I said that there is a difference between those who want a sign in order to believe, and those who He blessed because they already did. I also said that the shroud can never be proved as Christ's, and will also never make us better Christians. It's study is a waste of time.
In each case you listed above, the people were already accustomed to His miracles. The difference between them and the religious leaders is that they received His teaching. This is why He did the miracles.
The miracles were done to help illustrate a point, like Peter's faith (in the area of walking on the water). He fed the masses out of compassion, and the scripture tells us that in specific terms.
You can't demonstrate one miracle that He id that did not have a teaching hidden in the Spirit, or that told a hidden story. These were all done with the aid of the Holy Spirit, and it is His role to glorify Christ and teach us about Him.