Correct. It’s not a scam. Because it’s not free. The sandwich had a price posted, you paid it, you received the product. Valid business model.

What would you think instead if you saw a NYT front page ad taken out for Free Sandwich Mart, the all-you-can-eat totally free sandwich emporium?

Or in this case, a free browser extension that paid to sponsor five thousand YouTube videos that promises to help you pay less money to every store you activate it on at no cost to you?