The sun rises every day. I don't think it unreasonable for me to expect it to rise tomorrow. Yes, it may not. But it is still reasonable for me to assume it is going to.
Sure. So what?
This guy was well-known for stealing plants in the area and selling them for $2 on the street. He had stolen from the store before. He had never bought anything from the store. He had stolen earlier that day. He's now coming back to the store, after the owner had seen the video tape showing his earlier theft. Is it that unreasonable for the owner to expect him to repeat his crime?
Sure, it sounds like a reasonable suspicion.
Not sure what your point is.
I do agree that he should have called the police and let them deal with it.
Absolutely, and with the evidence above, it sounds like you would likely get a conviction.
But to lay charges, plea-bargain the real criminal down to nothing in exchange for testimony, and take this to court, in this particular case, with these particular circumstances? When no one was hurt? Really? Do you think that's reasonable, or justice?
It is absolutely right and just. We are talking about the conditions under which you can violate an individual's right to security of person, freedom of movement. To place someone under physical restraint is one of the most, if not the most, severe infringements of an individuals' rights that I can possibly imagine.
We must have very, very strict rules around when and who can use force against another individual, when and who and how such fundamental freedoms can be revoked.
Even the police do not have such arbitrary powers of arrest by no means, by no means whatsoever, should we accept a society in which any individual, based on nothing more than their own suspicions, can go around assaulting and confining other individuals.
Nothing could be more important than making an example out of this guy so that the message to all citizens is clear:
You cannot, ever, use force against another individual unless they are actually committing a crime right in front of your eyes that very moment.
Any other use of force must follow strict protocols of which the average person is ignorant. There is a reason we send police to training for so long as we do: So that they know when it is and is not appropriate to use force.