Well actually according to many dictionaries online scarfs is also the accepted plural form for scarf along with scarves.
I quote: Scarfs vs. scarves. Scarf has two plurals—scarfs and scarves. Scarves is the preferred form, but scarfs is the original and was more common before the 20th century.
Personally I've never heard it as a plural, but as the third person singular of the verb 'to scarf' or 'to scarf down' (eat enthusiastically).
Sometimes Norwegian is so much like English, that I'm able to guess the meaning without rolling the cursor over the word. I love that! Jeg elsker det!