It's misleading to say "a dollar or two" cheaper when that's almost 50% cheaper.
"Customers may pay anywhere from $3.75 for a Big Mac in Austin, Texas, to $6.39 in Seattle. For Cheeseburgers, the variation was even greater, from $1 in places like Chicago and Houston to $2.29 in New York City."
https://www.restaurantbusinessonline.com/financing/why-big-m...