That's mostly because the Independence Day director was known for being very cost-effective and frugal. It was a blockbuster, but didn't start as a big spending production like the Titanic for example.
But even that is 10 times what Fargo cost already.
Sub 10 million have been small peanuts in Hollywood even in the eighties, by Fargo's time a movie was not even taken seriously by big studios if it had such a budget.
Heck -- an A-list actor would command 10-15 million just for himself.
Burn After Reading had Brad Pitt and George Clooney. Can't get much more A-list than that. It also had John Malkovich and Tilda Swinton, who are no lightweights. And it came in at a budget of under 40M.
For comparison, a traditional american "happy comedy", Happy Gilmore released the same year, made a third less despite costing almost twice as much.