Lara Vapnyar, Still Here
Of course, he could accomplish the latter by simply reading Sartre in the privacy of his own room, rather than pretending to read it in public. But no, he wants to be seen by others, even complete strangers, reading or at least holding a high-brow book. The boost in self-confidence comes from the impression made on others. That's what will make him feel better about himself. It might also be a way to pick up women.
Many of us have been guilty of selecting books on the basis of the impression they will leave with others, assuming anyone even notices what book we have with us. Notice that Vadik takes his book to a bar. Most bars I have entered have been too dark to read in, let alone to make out the title of someone else's book.
The books we choose to impress will vary depending upon whom we wish to impress and why. A person may want to seen with the latest best seller. Another novel I am reading is set in the 1930s. Women aboard a liner heading toward Europe make a point to be seen reading Gone With the Wind on deck. Some books become best sellers, or remain best sellers, because they are books stylish people want to be seen with.
For people more like Vadik, who wish to be seen as intellectual whether they are really intellectual or not, some high-brow book will do nicely.
One problem with reading a book on an iPad, Kindle or whatever is that the title cannot be displayed prominently for all to see. Nor can they notice how thick it is. How can you impress anyone that way?