I am surprised that this article doesn't mention SG&A (Selling and general administrative expenses). For many companies SG&A are much larger than COGS and compr

I am surprised that this article doesn't mention SG&A (Selling and general administrative expenses). For many companies SG&A are much larger than COGS and comprise all the costs that are not included in COGS. So if companies have some discretion to include an expense item in COGS, they also have some discretion to include other expense items in SG&A.