I live in Alaska, so the AK Air cc is sort of a lifesaver for us. My husband and I each have one, and my husband's is tied in with our grocery store rewards card, so he gets a small "discount" on food, + airline miles. This works out for us because...well, Alaska. It's a state that's bigger than most countries, so we've got to fly to get anywhere out of state in a reasonable amount of time. (Driving to see my in-laws, at the bottom of the state, takes about 10 hours from where we are, in the middle of the state.) So, it works out well if you'll really use the points. It's hard to say an unequivocal "yes, they're awesome!" as I don't know your particular situation. For me, having free flights is how we're going to go see my family this summer so that people can meet the munchkin.
I don't really care about the data mining. Honestly, we don't buy too much from this particular store as we tend to get meat from a local butcher shop (or it's been hunted/fished by family), as many veggies as possible are homegrown/bought from the farmer's market, foraged, etc., and I make pretty much all of our bread so they probably think we're vegetarians who don't eat very much!
The markup on items concerns me more. Some things are just fine, but they charge $.90 for cans of cat food while the store across the street charges $.50. (As just one small example.) So you do need to compare prices, otherwise you'll end up getting swindled and then it doesn't matter how many free flights you get because you've essentially already paid for them.
The credit card is the most useful part for us. My family lives in the Lower 48, and it can be really pricey to visit them. Like, $800+ per ticket outside of the holiday season. (Don't even ask about Christmastime.) We just buy everything we need to on our credit cards, have our non-rent bills hooked up to them to auto-pay, and pay them off every month so we don't have to pay the astronomical interest rates. We've accrued quite a few free flights this way, even with our modest spending. Plus, I get one passenger discount ticket each year. As in, pay full price for one ticket and someone else flies for $50. We've never needed to use it ourselves, but we helped some family get here for our wedding because I bought their tickets using my discount and they paid me back.