Who says it's an addition of calories? For many people breakfast is just coffee with coconut oil and butter. It's not adding calories it's just consuming them at a different time. You're still going to be at a deficit at the end of the day.
For me it would be compared to just black coffee and no breakfast, so of course it would be additional calories if I force myself to drink coffee with butter in it.
In that case it probably doesn't make sense. Unless you find that adding it to your coffee allows you to not eat additional calories for a longer period of time.
