I don't think about the age of the packs. I use all gameplay items/mechanics that fit my storyline, regardless of the pack's age.
And some packs I knew that I would never, EVER use it's feature, such as University, Fame, and Running a Business because those things do not interest me.
That's like saying because children came with the base game, do we no longer play with kids since they've been in the game from the beginning. Not all of my households have kids (or want them) ..... same with pets, some households have pets, some do not because it's either too much bother because I'm busy with other things than to have to take care of a needy pet, or it doesn't fit my story.
