I'm pretty vocal about wanting seasons because my play style is very legacy style. I love taking one sim and growing a whole family tree. I know many find that boring and whatnot, but that's just what I love.
As others have said, seasons gives this sense of time passing. And just like I do in real life, when it comes to holidays like Christmas and New Years, I make my sims look back at their past through pictures and videos. The recording camera in the S3 was my best discovery of gameplay to this date. And I know many will laugh at that, but it just gives this sense that there's a history, and a deepness to their lives.
I dunno, maybe I think too much about this but seasons is simply the biggest game changer - literally - for me. It changes everything about how I play. I get so bored without it.
ETA: In my current legacy, I have a data storage unit with over 70 videos that my sims have taken. They're weddings, proms, birthdays etc. And over the holidays I really love having my sims look back at their childhood. It warms my heart :blush:
