Have just been looking on Amazon as I want to buy a set of measuring cups for baking. Saw an ideal set, however there is a rather strange warning given. "Not for sale to persons under the age of 18. By placing an order for this product, you declare that you are 18 years of age or over. This item must be used responsibly and appropriately."
I only discovered Amazon a few weeks ago, but I think they are great. I had trawled through every shop in town with no success for a couple of domestic items, viz egg cups and soup spoons. Found them on Amazon and they arrived the next day.
I suspect that the seller also includes knives in their product range and the same text has been appended to everything they sell.
Alternatively perhaps they've remembered that the average kitchen contains quite a few hallucinogenic substances (especially nutmeg), so perhaps they don't want minors using their measuring cups to gauge the intensity of their legal highs?