No Laundry?

[CSquared2]

Well, there we're different, amyrose.     I've never known a butler or maid to start laundry, but they'll finish it if I ask one of the family to start it.

[kattiq]

They usually start the laundry but never finish it! The maid/butler will go around and pick up some of the clothes and leave before the clothes need to be put in the dryer.

[MoMoll]

My male butler always did the laundry from start to finish; but, the female butler only sat around drinking coffee. Never had a maid do anything at all, except sit around.

[Hosfac]

Absolutely certain.  I mean, if the moodlet is 12 hours and my sim doesn't change clothes for 14 hours, yes, it'll run out, but as soon as she changes clothes it shows up again.  It also refreshes if she changes sooner.  I've never known a sim family in my game with laundry facilities not to be like this.  I really thought that's how it was supposed to work.  I'll be very surprised if I'm just the lucky guy who got the super helpful glitch!

I can confirm that this does happen, and I can confirm it's not a glitch.  I'm not entirely sure how long you can continue to get this buff without actually doing laundry, but I do know that eventually you'll stop getting it until you wash clothes again.  I can also say that with the washer upgrade, changing clothes will actually restore a bit of hygiene as well.