Not Regulating Body Temperature

This one is clearly reserved for the reptilian, amphibian, and fishy pets, for whom cold-blooded isn't just a way to describe your ex, but also a physical condition. Any pet owner who's ever bought a heat lamp or a heating pad knows how little control geckos, snakes, turtles, frogs, toads, and fish have over their body's temperature.
Why? Because they're lazy, lazy, lazy ectotherms. You know, when I was kid, lizards would walk twenty miles in the snow everyday just to get a heat lamp, and the heat lamp would only be 20 watts, but they made due with what they had. Nowadays these spoiled brats expect us to wait on them hand and foot. "Um, excuse me, but I'd like the lamp to be 80 watts, not 40. Otherwise I get lethargic and my body processes slow down significantly and it's bad for my health and it's possible I could die." Well, lizard, maybe you should thought of that before you became cold blooded. The rest of us are warm blooded and it's pretty damn sweet.
(flickr photo Green Gecko by dominigs81; http://www.flickr.com/photos/dominiqs/1349256667/)

Insect Eating

Dogs and cats will occasionally swipe a fly out of the air, but if you have any pet lizards or frogs, you know they eat insects all the goddamn time. They eat insects for every meal. That's just nasty. What's wrong with them? Don't they know bugs are gross? Wouldn't they rather have a nice fillet mignon with a baked potato and caesar salad? Maybe a little wine? Some cabernet, perhaps? Apparently not. Seems they'd prefer to gulp down live larva and some cold water out of a rock.
You could never show up at a party chomping on a grasshopper. Unless they're covered in chocolate or something else that drowns out the taste of grasshopper. And even then it's still weird. Get some chocolate-covered raisins, you freak.
(flickr photo froglet eating a worm by her wings; http://www.flickr.com/photos/herwings/2123121403/)