This very rarely happens in MA, because when it does the store has to give you the item for $10 off, including if that makes it free. And they have to post a sign at the register explaining the law, which means when you're invoking it all you need to do is point at the sign.
https://www.mass.gov/info-details/consumer-pricing-accuracy-...
I wanted to purchase a laptop at the advertised price. The sales person told me i was in luck, because all their laptops came preinstalled with Microsoft Office for a little extra money. I told him politely i did not want to buy Microsoft Office, even for such little extra money. I just wanted the laptop.
Semi-flabbergasted he told me this was not possible, because all the laptops had Office pre-installed. I told him i did not care and wanted to buy the laptop for the adverstised price.
After 15 minutes of discussion, some manager came frustrated what the problem was. I pointed to the price tag and told him i wanted to buy the laptop for that price exactly and if that was possible. It was, but it would require uninstalling Office, which took them another 15 minutes.
So i waited for another 15 minutes so they could remove Office. Back at home i powered on the laptop, popped in a usb disk and removed every partition that its harddisk ever had and started a nice fresh install without any bloatware.
There are of course exceptions; I can recall not long ago for example buying a pound of Himalayan sea salt for a dollar. That was a solid deal, and I haven’t seen it since.
But generally speaking, if you want to save money, don’t go to Dollar Tree.
With your focus on calories per dollar, do you also get supplements? Which ones and where?
Why are you so focused on this?