Admitted, the (DBA) should not be in the title. But of the players of the DBx series, noone says 'De Bellis [Antiquitatis|Multitudinis|Renationis]' but 'DBA|DBM|DBR'. At least I don't know a single player of these games who uses the full name. As opposed to Ticket to Ride, where I know only one single player (who for a long time mostly played games on BSW) who would use TtR in spoken language.
Indeed, in fact I'd go as far as to suggest that there are plenty of wargamers out there who have never heard of the full names of De Bellis Antiquitatis or De Bellis Multitudinis. Many folk will be aware of the games only as DBA or DBM. I think it makes sence to have the abbreviation in the title for the purposes of searches.