<p>“I’ve seen people turn down $80 dinners at the faculty club (to which they were invited as guests) because they were too busy.”</p>
<p>By the way, if I may add my own advice, that’s usually not a great move, even leaving aside the excellent food. 
I’ve had more interesting conversations with professors over meals than probably at any other time. This dovetails nicely with Ben’s #19.</p>