Chili's, for instance, serves not only freshly made salsa but freshly fried chips. The tortillas are pre-made and pre-cut and just need to be dumped in the oil, and you can make salsa in batches by dumping pre-measured portions in a blender. Panda Express is cooking everything on site throughout the day, too. Take the right bags of pre-cut vegetable blends, the meat, the sauce, stir it all furiously in a big wok, put it on a heat table. No microwave.
Most of the speed of "casual" restaurants just comes from doing a lot of prep work ahead of time, keeping everything from sauces to precooked vegetable mixes in warmers, and using the same ingredients across a range of dishes. (Prepare five grilled meats, six sauces, and put them on beds of rice, mashed potatoes, or pasta, and now come up with a name for each possible combination. Presto! You're a Cheesecake Factory.)
Ones that I would argue don't want to be looked down upon (but are) are the likes of Olive Garden, Chili's, Applebees, Texas Roadhouse. They put on a facade of being fancy, but everyone knows most dishes served at these places were frozen and put in the microwave minutes before they are served. I could be wrong with the examples I gave though; it's been a long time since I've eaten out at any of them...