(DEVIL'S ADVOCATE) Am I allowed to go to businesses and try to pick the locks, look inside, and then report to the business owner that their lock was pickable? Well... yes, but I'd probably be reported to police. Websites, like locks, aren't bullet proof. How many web applications out there don't have a security flaw somewhere? Doing penetration tests on unwilling victims is risky. Trying to break wifi, company intra…
Sometimes these discoveries aren't intentional. Let's say I lean against a door and it's not locked. Well, I never meant to open it up, but since I can't prove I didn't intend to, and since the business can't distinguish people with honorable intentions vs. those without, why risk telling them?
If you tar the helpful with the same brush as the crooks then you shall always learn the hard way from your mistakes.