It is almost beyond belief that this works so poorly. I generally don’t even bother to keep track, although every so often some miles materialize from a retail purchase.
That said, in researching a large upcoming purchase and making sure that my credit card information was correct, I couldn’t help but notice that I don’t get miles for any number of places that I shop at anyway. Small amounts, to be sure, but it looks to me that I might get miles for maybe 1 out of 4; probably closer to 1 out of 10 purchases.
Compare this to Rewards Network, the dining program, which has a failure rate of about 1%, most of which are the restaurants' fault, I believe. So, there is no technological reason that this portal is so shoddy, and I suspect that they could right the ship if they cared to, so after I get miles on my large purchase (enough that I’m prepared to argue for ‘em) I’ll try to find a replacement for this crummy portal.