I'm surprised to hear that taster flights seem trendy. I've seen them at pretty much every brewpub I've been to, and if available I always order one. I'd rather be able to sample 4-6 of the beers being offered than be limited to the 2 or 3 I would typically get over the course of a meal.
Plus, I get a taste of beers I'd rarely order a full pint of, but am interested in tasting. For example, I'm not generally inclined to order a fruit beer or a blonde ale, but I'm generally the one my non-beer nerd friends turn to for recommendations. I like to steer them in the right direction. Also, something like a light lager or a blonde ale is a pretty good indication of a well-run brewhouse when done correctly.