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It depends on where you shop regularly - if you hit the same store multiple times a week, the discounts and rewards add up quick enough to justify it, but if you're bouncing around different places, you'll forget about the points anyway. I signed up for a few programs out of habit and only actually use the ones for places I genuinely go to often.
How often do you actually remember to bring your phone or card when you shop? I've been in the loyalty game for a few years now, and honestly the math works out only if you're genuinely shopping at the same place regularly enough that the rewards stack up faster than you forget you have an account. At my local grocery store where I go weekly, I've saved maybe a decent chunk over time on things I'd buy anyway - but at places where I visit once every few months, the whole thing just sits dormant and I end up missing deals because I never check. The real question isn't whether loyalty programs work in theory, it's whether you have the actual shopping habits and follow-through to make them work for you.
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