That’s not exclusive to LAS pairings. I’ve done 4 and 5 legs occasionally out of FLL. I personally avoid anything that has more than 2 legs a day but once in a while, I have swapped for those crappy trips just to accommodate last minute changes in my personal schedule. I didn’t suffer much on those days since I rarely have them though. On an everyday basis would be a much different story.

Also despite LAS crew’s imagination, they’re not the only ones being hammered by red eyes. The rest of the bases are also carrying the load, even with 2-leg red eyes.

For those trying to make it over to Spirit, keep in mind that red eyes are part of our lifestyle now. Once you’re senior you can avoid them. The occasional one leg trans-con won’t kill you.
If you are the kind of person that can’t handle a red eye at all, please reconsider your options. We’re in the business of lowering costs, which means flying the airplanes round the clock and optimizing gate space.

This surely is becoming the airline that never sleeps. (Nor our passengers for that matter)