It is certainly courteous and proper to avoid supplying alcoholics with alcohol in any form or amount when practical.
However, it is extremely unlikely that the minute amount of alcohol in most cooked recipes, in flavor extracts, or in proper dosages of a large number of medications, is sufficient to adversely affect most alcoholics.
Alcohol has been given something of a bad rap by many who are opposed to it in any form, at any time.
Alcohol is a naturally occurring substance: it is common for over-ripe fruit and berries still on the tree or vine, subjected to the ever present yeast spores, to ferment precisely like wine. Birds and animals have been documented and filmed somewhat tipsy from imbibing too much. [Note that the yeast used to leaven bread converts some of the sugar to alcohol, which is totally evaporated by the baking process!]
A large number of clinical studies by very reputable researchers has shown alcohol in small to moderate quantities to be quite beneficial in a variety of human conditions. Red wine has been proven particularly beneficial – possibly because of other substances aside from the alcohol.
In foods, or in alcoholic beverages, for that matter, the sought flavor is not of the alcohol, but of other flavors that are associated with it, i.e., the vanilla flavor in its extract, or the “rum” flavors in rum, etc. Vodka, which is essentially ethyl alcohol and water, has little flavor of its own, which makes it so popular for mixed drinks where the desired flavor is added. Few people – if any –enjoy the taste of pure alcohol.
Lastly, to correct an erroneous impression mentioned earlier, in a mixture of alcohol and water (such a “booze”) both evaporate in air. However the alcohol evaporates much faster than does the water. Using a mixture of half alcohol and half water, if left open in air, even at room temperature, the alcohol will have evaporated almost completely before an appreciable amount of water will have done so.