I disagree. She was given gifts with no thought behind them. It seems obvious that that was the problem, not how much they cost. If we gave her a gift that she likes and we had clearly put some thought into, you really think she's going to get upset because she might perceive it as expensive, despite how often she's marvelled at how rich our world is?
Of course you can, it's your opinion. Although I do think giving someone a gift and expecting something in return, like loyality, obedience or body, is rather bad intent.
I know my english isn't perfect, I do know I'm making a lot of mistakes writting my posts, but I do think I'm using rather important phrases, like "may be" not "will be", "she might", not "she will". I'm writting she "might be" upset with MC, because she" might" see it in that way, even if she acknoledge of differences. Not she "will be" upset with MC, because she "might" see it that way, even if she she acknowledge of differences.
And yes, I do think she might get upset with MC, because of expensive gift. But not because expensive gift is expensive, but expensive gift is a gift she used to recive from royal douchebags. Thus, MC giving a gift she may consider expensive could be precived by her as another douchebag objectifying her. And not because she wants, but because she is used to it. Thus, expensive gift = another douchebag.
People bringing up the idea that Rae may consider books to be very expensive, are forgetting that Rae has been studying the MC and his world as much as Cait has. The discussion about the library would have come up, if not in the game, then definitely offscreen as well as the discussion of books being widely available.
Yes, they studied MC's world, but they only studied it. They are still from the different worlds, from worlds where things work in different way, have different political system, different item accessibility, different prices. Because MC said "You know, those things are pretty common in my world, you can basically buy them in any store" one or two times won't magically stop Cait from happily awing at every single book and Rae from being astonished by fashion magazines until they just get use to it. To MC those things are common, to them they are not. But in order to fully understand MC's world they would have to live there for a while, not just study it from a house in the void, athough it is a good, and safe, place to start.
Also, lets not forget that Rae is incredibly intelligent. She has seen that the MC comes from a technologically advanced world and has been shown to come up with accurate deductions with just some scant information. If the MC tells her that books are common on his world, than Rae should be able to discern that there is a means to both create and disseminate those books on a large scale.
She is because she have, well had, to be in order to survive on many different worlds. But, as I wrote a little above, she won't magically stop being astonished, because of the knowledge. Because she knows books on MC's world are common and pretty cheap for anyone to aquire, doesn't mean she won't consider a cookbook by her's world standards, at least at first.
Again, its the intent of the gift that Rae will recognise, not the cost. Rae has an interest in cooking, especially when the MC helps her. She also has an interest in fashion and in the history of the MC's world. Any item that tapped into those interests will probably mean much more to Rae than yet another gold trinket.
Of course she will recognise the intent, but because of her past, of royal douchebags giving her expensive items , she might consider first the price of a item (expensive = douchebag) and get a bit upset with MC before recognising his intent. But with the rest of your comment I agree.