Flip-tops typically have a little notch for your finger. If that caught on something while putting it in a bag, there would be more than enough force to open it. I’ll stick to screw tops.
Could be just the lingering trauma of said shampoo bottle a long long time ago.
I do have a subconscious habit of checking that screwed on caps are actually screwed on when putting them away
fair enough. I sometimes put things that can get caught on other things, inside a plastic bag and twist the top tightly, to try to avoid this.
I too always check lids. My partner consistently leaves lids loose on things, so it depends on the person also.