Unfortunately the airline industry is both filled with caches upon caches upon caches when it comes to prices and also deceptive dark patterns.

The dark patterns have got better over time (as meta-search like Skyscanner and Kayak drive so much traffic to sites and demand honest pricing - travel agents either have to clean up their act or forgo meta search traffic) but the many, many layers of caches remain.

That sucks, but to be fair that's not usually intentional, but simply a cached price that hasn't updated. You see this especially with flights for some reason due to the complexity -- airlines change prices incredibly frequently but aggregator sites can't refresh them all instantly. I'd forgive a site if I only saw this happen once/occasionally, but I'd report it to regulators if I saw it happen as a pattern.

With how laggy those sites are, I figured they are indeed pulling the price from the origin... Interesting that they'd have their own cache and still be so slow.

Can’t recall where I’ve heard it, but that lag is almost always artificial—meant to convince the user that time was spent finding a good deal.

Not updating the cache before/when asking for CC information is at the very least knowingly ignoring the problem, and likely intentionally ignoring the problem because the user is more likely to continue anyway once you've tricked them into giving their CC information and they just need to click yes to be done...

I hope jurisdictions that have "truth in advertising" laws bring the hammer down on such "negligent" violations.

That looks to be a classic bait-and-switch, which is considered a form of fraudulent advertising in many jurisdictions. It may not be worth the hassle for you, but you probably could report them if you want.

Probably depends on whether the entity baiting you is the same as (or represents) the entity you're ultimately purchasing from. If the aggregator is merely redirecting you to the airline and getting a kickback, as opposed to actually being a middleman, maybe that's a loophole in bait-and-switch law?

On the other hand, since GP furnished payment details to the baiter, I guess it really is a middleman, in which case you're absolutely correct.

Delta was doing that to me a few years back. I was so frustrated I called them to complain and actually got the ticket for the price they advertised. Still annoying when you go through the checkout multiple times on different days only to get the same not available anymore alert.

Name and shame, please!

... so that others do not have to go through this experience ...