That is how illustrations work. If someone doesn't see something, you amplify it until it clubs them over the head and even an idiot can see it.
And sometimes of course even that doesn't work but there has always been and always will be the clued, clue-resistant, and the clue-proof. Can't do anything about the clue-proof but at least presenting the arguments allows everyone else to consider them.
This fixation on the reverence due a spouse is completely stupid and beside the point of the concept being expressed. As though you think there is some arbitrary rule about spouses that is the essense of the problem? The gift-for-spouse is an intentionally hyberbolic example of a concept that also exists and applies the same at non-hyperbolic levels.
The point of a clearer example is you recognize "oh yeah, that would be wrong" and so then the next step is to ask what makes it wrong? And why doesn't that apply the same back in the original context?
You apparently would say "because it's not my wife", but there is nothing magically different about needing to respect your spouses time vs anyone else's. It's not like there is some arbitrary rule that says you can't lie to a spouse simply because they are a spouse and those are the rules about spouses. You don't lie to a spouse because it's intrinsically wrong to lie at all to anyone. It's merely extra wrong to to do anything wrong to someone you supposedly claim to extra-care about. Lying was already wrong all by itself for reasons that don't have anything special to do with spouses.
This idea that it's fine to lie to and waste the time of everyone else, commandeer and harness their attention of an interaction with you, while you just let a robot do your part and you are off doing something more interesting with your own time and attention, to everyone else who isn't your spouse simply because you don't know them personally and have no reason to care about them is really pretty damning. The more you try to make this argument that you seem to think is so rational, the more empty inside you declare yourself to be.
I really can not understand how anyone can try to float the argument "What's so bad about being tricked if you can't tell you were tricked?" There are several words for the different facets of what's so wrong, such as "manipulation". All I can say is, I guess you'll just have to take it on faith that humans overwhemingly consider manipulation to be a bad thing. Read up on it. It's not just some strange idea I have.