Can alcohol be substituted for sugar?

We have two elderly sisters that insist on giving us a fifth of our favorite drink for Christmas.  I think they forget we tell them not to and I don't want to badger them about it.  In years past that was not a problem but now my husband and I are both diabetics and it is simply not worth the extra calories to drink anymore so as a consequence we have several bottles of scotch and amaretto in the cabinet taking up space.   I know one solution is to pass them on as gifts and sometime I do but I have been thinking about using them to cook with and I wonder if they could be used in place to feed yeast or if that wouldn't work.