Stop keeping company with anyone called a brother who is sexually immoral or a greedy person or an idolater or a reviler or a drunkard or an extortioner, not even eating with such a man.”
Note the words idolat-er, revil-er, drunk-ard and extortion-er. Clearly this is referring to habitual practisers of these things. Certainly not one-off sins or even those prone to occasional lapses. I would suggest that most folk with any common sense would probably choose not to associate with such persons anyway, let alone stick their fingers into the same communal eating bowl. Also note the admonition to avoid keeping company with such people. Nothing there about pretending that they don't exist as happens in disfellowshipping.