plenty of other reasons, i.e. performance, programs to run, customer service and how long they last. You can get a macbook air for 900 as a student (or a used one for cheaper). obviously I'd look at either the 13 in macbook air or 13 in macbook pro...both are good and light.
Its a preference, but they do last longer so you technically save money. You can also sell a used mac when no one would buy a used pc.
Last of all, they do have full-sized keyboards (unless you're talking about the 11 in MBA, which has the biggest keyboard of an 11 in)
But, yeah, its preference. (and classiness, and style, and...ok Im biased
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