I think this has been an interesting thread, and I see things from other's perspectives and even though they may differ from my own, they each make sense to me.
I think it's about motive. I used to stop myself sometimes and question my motive for doing things. If it was to make my son's life easier or something that I thought might help him to get clean then my motive was control, trying to control HIS future...which of course was never mine to control. But if it was about my own feeling of well being, then I went ahead and too bad what he thought.
I had boundaries and rules when he lived at home. One was that if I even suspected that there were drugs in MY house, all privacy was tossed to the wind and I would search wherever I wanted to remove the drugs...and if found, I would remove my son from the house too. He could do what he wanted anyplace else, but my house, my rules. I didn't make myself crazy playing codie detective, but if the signs were there that there may be drugs in his bedroom (like when he came out with pupils much larger than when he went in), the search was on.
That was to protect ME, having drugs in my home was a deal breaker because it put me in jeopardy too.
Checking my motives is something I often do even today, in life's situations. It's amazing how many times I need to pause and give thought to this and I suppose I should be grateful for all the practice my son gave me.
You have children, that adds to the equation. Keeping them safe is number one so clearing all drugs and/or paraphernalia is a wise thing to do.
I don't think that you believe that removing this stuff or checking the shed out back will change the outcome of whether he will use or not. You already know that nothing we do or don't do will make a lick of difference for them...but sometimes it does make a difference for ourselves.
This post got long, I didn't intend that, lol, just ponderings from this codie's mind and sharing the thoughts here.