Briggs & Stratton 30W Engine Oil 48 Oz (for mowers, tractors, pressure washers etc.) – $5 + taxes on Amazon (as addon item) or Walmart

Briggs & Stratton 30W Engine Oil – 48 Oz. 100028 is for $5 on both walmart or Amazon (as addon item).
This seems like a good price for engine oil coming from Briggs & Stratton.
Everywhere else, even 32 oz oil from even unknown companies is sold at higher price.
Link:
Amazon:
https://www.amazon.com/gp/product/B000BXOGMY/
Walmart:
https://www.walmart.com/ip/Briggs…z/16778644
Product description:
Briggs & Stratton 4-Cycle Engine Oil 48 oz is specially formulated for small engines. It is ideal to use for lawnmowers, tractors, generators, pressure washers and outdoor power equipment. The Briggs & Stratton engine oil is classified SJ/CD by the API.