Something weird is happening with airline pricing
I'm researching some flight options for my upcoming trip and I've been noticing some discrepancies in pricing for the same flight.
A multi-city priced cheaper than a one-way
I'm looking to travel LAS-SFO on American Airlines, with a layover in LAX. While the 6PM departure is only $219, the 10AM departure is at a much higher $388. While I know I can always book the later flight and standby for the earlier, I'd much rather have confirmed tickets in hand ready to go.

So I did a little experimenting. I tried different city pairs, different VPN locations, but nothing booked as a one-way would come up to a cheaper price. However, I found that if I pieced together both flights as a multi-city itinerary, I could get the price down to $219. That's right - same flights, same day, same order, but $169 cheaper by changing how it's booked...

Now this makes absolutely no sense to me. Why on earth would the exact same flights price completely differently? Was it because the individual flights were much cheaper, and AA simply didn't want anyone booking that connection?
Well, no. The individual flights were MUCH more expensive. Just LAS-LAX alone was about $250, then LAX-SFO was about an extra $150.
It would make sense if the converse were true. If the multi-city flight was more expensive because it sums A+B, that would make sense. But here the A+B price was less than booking together.
And my flight from LAS-SFO wasn't the only example I found! I spent an hour digging and found plenty more examples.
Sidebar - skiplagging (the opposite of what's happening)
Many of you probably already know about "skiplagging" - where a traveller might book an onward ticket and getting off at their connecting airport, simply because it's cheaper. This makes sense due to the laws of supply and demand.
Say for example American knows a passenger flying PHX-DFW has few good options, but PHX-SDF is more competitive. They would price PHX-DFW at $400 and PHX-DFW-SDF at $300. A passenger who "skiplags" buys the cheaper ticket and just doesn't travel the second leg. Airlines prohibit this practice, but it makes sense why this phenomenon happens.
But whatever on earth is happening with the multi-city debacle? I honestly have no idea.