Don't you wish we could use all of the outfits for every occasion/season?

Up at the top of the CAS catalog, it lists the filters being used. Turn off the one for the season (cold weather, hot weather) and use whatever you want. As long as it's in the hot/cold weather slot, it will keep your sims cool or warm as needed, even if it doesn't look like it. Put them in a parka in their hot weather clothes, or a bikini in their cold weather clothes.

You can do that. Just x out the filter at the top and the whole wardrobe becomes available. My sims hardly ever use the formal tab for actual formal occasions. I use that tab for character wear (Spellcaster wizard wear, elven outfits, etc). Just be aware that whatever is in the filter tab will be used by the game for situational wear. Your sims won't know the difference, and as long as it's in the slot for the season they'll be okay, weather wise.

I had no idea---thanks, guys!

Yeah, I just learned this just the other day. And how long has Seasons been out?? :D