It is perfectly possible for emergency codes to be used, in order not to panic the people inside. e.g. A well known large public building in London (used to have?) in the event of (say ) a bomb threat, "Will staff members responsible for administration, report to room 99." This meant the you had to search your area for suspicious ityems and report in if anything found. A perfectly innocuous announcement to all but those in the know, but getting the message to those who needed to act.
Yes, but you are rather missing the point.
The code isn't meant to deceive passengers, they will be informed as appropriate once time permits. The code is intended to get the crew to follow a particular drill appropriate to their individual and collective crew stations, with the minimum amount of communication at that point.
The flight deck crew are busy with their priorities at this point. Those priorities are first and foremost to fly the aircraft and deal with the problem. Ensure the aircraft flies a safe profile, and to communicate as necessary between themselves and ATC in pretty much that order. (Aviate, navigate, communicate.) Depending on the nature of the problem the "communicate" function may well involve the cabin crew quite early in the process, and the passengers somewhat later, once the immediate priorities have been satisfied.
Code words are used to instigate the cabin crew actions with very few syllables in a couple of perhaps repeated words.
Will staff members responsible for administration, report to room 99!
May be great in an office building, but frankly 21 syllables of delivery is inefficient and pointless in the context of an aircraft emergency.
To be clear, the use of codewords is for brevity in instructing a set of actions. It is not for placating or misleading passengers, many of whom would likely be aware of a problem in any event. To that end it works well and is standard operating procedure for many airlines.
If it offends your sensibility as a passenger, then sorry, but safety is paramount to your immediate concern, the latter hopefully being addressed once the former is guaranteed.