If I was on any such jury I would agree that it is indeed reasonable to suspect theft if someone refuses to show their receipt. "Reasonable cause" is not the same thing as "proof of guilt", and I think that's where you're getting confused. If there is reasonable cause, then they CAN detain you until it is sorted out. If the customer wants to PREVENT it being sorted out by simply showing the receipt, then tough luck for him... that was HIS choice.
Well like it or not you would be in the minority, and fortunately not only that, the judge wouldn’t let it stand.
Private citizens or businesses do not get the right to hold people against their will just because they FEEL like it. Refusing to show a receipt is not probably cause for a CRIME.
The law allows folks to be detained ONLY if they have reasonable reason to suspect them of a crime, refusing to show them a receipt is not remotely probable cause. The threshold to allow a private citizen to be held against their will is far higher than the fact that some schmuck doesn’t like the fact you won’t show him a receipt for a product you paid for.
To think that somehow the barrier to be imprisoned should be so low shows just exactly how successful the leftist have become at dumbing down the general population. No one, no one has the right to detain you against your will without damned good cause, to believe that you are a criminal, refusing to show a receipt does not remotely meet that barrier.