As soon as you buy something, you get ads and emails telling you that you need more of the same.

DEAR AMAZON, I BOUGHT A TOILET SEAT BECAUSE I NEEDED ONE. NECESSITY, NOT DESIRE. I DO NOT COLLECT THEM, I AM NOT A TOILET SEAT ADDICT; NO MATTER HOW TEMPTINGLY YOU EMAIL ME, I AM NOT GOING TO THINK, OH GO ON THEN, JUST ONE MORE TOILET SEAT, I'LL TREAT MYSELF