I tend to avoid rewards cards. The ones you get at the grocery store that give you discounts on certain things, the ones that you get at the coffee shop that give you a freebie after ten or twelve coffee — they’re not my thing.

This decision to generally avoid these programs stemmed from my desire to control my inner, decision-making math, at least as much as is feasible.

That is to say, I’m aware that when we make purchasing decisions, we tend to very quickly slam a bunch of numbers together in order to decide what we buy and what we don’t.

These numbers come from all over the place: the cost of the item in question; the cost of comparable items; the implied savings or loss resulting from a purchase or non-purchase; the relative status gained or lost by going with this brand over another; the amount of money available in one’s bank account, or the amount of cash in one’s wallet or purse; the sale price versus the non-sale price; the numerous visual and non-visual cues (music and smells and the color of the walls and warmth of the lighting).

There are already plenty of variables influencing how I buy, and most of them are things I can be aware of, but can’t completely control.

Rewards cards and things of that nature, however, I can.

Yes, it could be argued that I could save money by getting that thirteenth coffee free. But it could also be argued that, in little ways, I’m surreptitiously being nudged toward buying more coffee, and more coffee from that one coffee place in particular, because the part of my brain that measures and weighs my purchases is being swayed. When I go through that split-second process of deciding how best to spend my time and money, the mathematical equation I throw together without even trying has a new, covert factor involved, and that factor inches me toward ‘buy.’

I’m not saying these reward programs are anywhere near malicious.

But I do think that being aware of how they influence our decisions is important, because a familiarity with the knee-jerk math we do in those few seconds we typically take before making a purchase allows us to make better choices in general, not just with groceries and coffee.