There have been a variety of reasons that have been ennunciated to support the idea of when to drink. I , for one have categorized malts according to the following table:
Breakfast Malts - mild - Lowland?
Lunchtime Malts - flavorable, but not overpowering
Afternoon Malts - "good sippin' whiskies
Evening Malts - Pretty much anything goes.
Trauma Malts - generally heavy peated
Celebration Malts - the "good stuff"
Since the above table reflects an accompaniment to food, this makes drinking part of the meal( a symphony of flavors ) and hence possible thru'out the day without the feeling guilt!