I'm poor and live right next to the grocery store, which is kind of a sweet combo! For financial reasons, I wait as long as possible to buy something I need, and I only have to walk 5 min (or drive if it's -8F like it was today!!) to the store to pick it up. Consequently, I don't really have many things that go bad.
I buy the smallest quantities I need, and buy frozen when I can. For fresh things, I always make sure they're in a clear container (like clear tupperware or glass storage containers). I also clean my fridge out pretty regularly (at least once a week) not only to get rid of any old things, but mostly because I need to free up some tupperware! Just a general rule that I use when it comes to fridge storage: put larger things near the back, smaller things near the front.
I've been to Trader Joe's a few times, and wasn't overly impressed. Maybe I just wasn't looking close enough, but things didn't really seem any cheaper than what I could get at my local Kroger. Also, I don't know if its just the Trader Joe's near me or all Trader Joe's, but I didn't see any fresh meat there. They seemed to be more centered on a vegetarian lifestyle than a primal one. (Just my impression.)
I hope this helped a little bit!