1. Like most people, couponing. I will very rarely do a diaper deal, or pick up a genuine freebie (I paid nothing for a tube of toothpaste last week at CVS, and no messing around with ECBs or anything). Otherwise, I stay away. It's particularly bad in NYC. The inserts (and I have access to like 10 newspapers a week) don't have all the coupons that other places do, and we have a lot of tiny independent chains, so it's not like you can go online, look at a matchup, and quickly pick deals. I shop at Costco, Aldi, my hometown guy for meat and in dire times of milk emergencies, the expensive grocery store across the street.
2. Non pod-based espresso making systems. If my husband won't use it and goes to Starbucks instead, that's not a cost savings.
3. Thrift store clothes for me. I rarely found things I liked and would rather catch a good sale on something new, go without, or buy used on eBay for a bit more, but be able to seek out exactly what I want. It's a better bet for the baby and housewares. And I hate shopping and thrift shopping seems like the least efficient way to shop.