Alaska isn't as (ok I will say it) fraudulent about this as others, notably the big 4. There are several 1-stop SEA-(hub)-Europe flights that carry the same flight number all the way through. What is irritating about these is that they generally include a change of aircraft, but not a flight number. It is essentially the same as using two different flight numbers. Mostly it is done to show up higher on GDS flight displays, but it is a rather fecal policy. (I can't type ...... here).

The only time this hasn't dinged me was recently flying EZE-ATL-LAX. The flight is #110 all the way through, but changes from an A330 to a 777 at ATL. It credited as two segments only because, as far as I can tell, the flights were on two different dates. Not complaining. It was an extra 900+ miles (and 900+ mile more as gold bonus).