Not all reactions are in textbooks and not all reactions in textbooks are general reactions, so no importance should be given for an absence per se. An absence of a reaction can mean the reaction fails, for example para nitration of methyl benzoate as the major product. Basically, one shouldn't put too much importance if a reaction is not in a textbook.
Reactions in which water or an alcohols are nucleophiles are controlled by le Chatlier's principle and not by a kinetic superiority of either. In an amide to ester con :larrow:version, a similar argument can be made. While an amine is a stronger base, hence poorer leaving group, it is also the stronger base in the tetrahedral intermediate. Therefore, the nitrogen will be protonated to a greater extent than the oxygen. A neutral alcohol is the leaving group on acid and not an alkoxide. An ammonium ion giving the free amine is the better leaving group because there will be less oxonium ion than ammonium ion in the intermediate.
In acid, the amine leaving group will be protonated to from an ammonium salt, thus tying up the amine from competitive nucleophilic attack.