You, the store owner, may know that; but how do I, the customer, know it? How do I know you aren't selling data from that CCTV camera to others, who don't own your store and don't have the use for the data that you do? Even if you aren't doing that today, how do I know you won't tomorrow, when someone shows up with an offer you simply can't refuse? And so on and so on.
You're right that this is a sad situation, when people's desire for privacy means cutting off access to data even for the (few, I suspect, but still...) store owners who actually want to do something with it that might benefit the customer. But it's what we have. If you want to know where to put the eggs, you'll have to figure it out some other way.
You, the store owner, may know that; but how do I, the customer, know it? How do I know you aren't selling data from that CCTV camera to others, who don't own your store and don't have the use for the data that you do? Even if you aren't doing that today, how do I know you won't tomorrow, when someone shows up with an offer you simply can't refuse? And so on and so on.
You're right that this is a sad situation, when people's desire for privacy means cutting off access to data even for the (few, I suspect, but still...) store owners who actually want to do something with it that might benefit the customer. But it's what we have. If you want to know where to put the eggs, you'll have to figure it out some other way.