I mean, if you’re really concerned about people buying more than they need, just so say on your site - obviously a valid concern and don’t think any reasonable person would be offended by a reminder that everyone can make a difference by individually making an effort to do what’s right for them AND everyone else too.

Oh no, sorry if there was a misunderstanding. I said "sadly" because it is so unfortunate that we are all in this current situation -- a pandemic. And it feels "sad" in this specific context because I am seeing an uptick in searches for toilet paper, a result of people being unable to find it anywhere else. It's a sad state of affairs all around. I have no judgement on people buying extra toilet paper.

Do you compile this info manually or do you scrape Amazon? If you scrape, how do you get around the blocking restrictions?

I do not scrape Amazon. That would be practically impossible, especially if you want to keep your costs low.

I utilize their product advertising API, which provides enough data for my needs (since I'm not interested in every single product and I only update once a day presently).

The manual part is figuring out how many units are in each item. For Lego, it's pieces. For Poptarts, it's individual pastries. For toilet paper, it's individual sheets of TP. Every product is slightly different, and it's often times not obvious. Once this manual part is done once for an item, I never have to do it again -- it gets an updated price from the API, calculates the unit price (because it already knows the total units), and then it updates the website.