This is a dispute about who is the rightful owner of the Lego. That is a civil matter to be decided by the courts. Doesn't matter how clear the evidence, such disputes are for the courtroom.
Absolutely - and there are bad actors here that we should be mad at since they are abusing the law enforcement system but the default goal in situations should always be to de-escalate to prevent violence. I think the cops could have done a better job at explaining next steps and routes to approach a civil resolution but anyone objecting to the police officer removing Ben from the store property after a trespassing complaint doesn't understand how abusive it can be on the receiving end of stalking or harassment.
Separating parties in a civil dispute is always a good idea.
This is a dispute about who is the rightful owner of the Lego. That is a civil matter to be decided by the courts. Doesn't matter how clear the evidence, such disputes are for the courtroom.