I've had firesdays where I don't see a single geode/ifritite on THF, with TH7+. I'll generally pull 1-2 of them with any luck whenever I feel like dropping everything to camp Firesday when it rolls around during the times I'm online. I got 3 geodes one time, and that was on PUP/THF with TH 3 (tarutaru sash)... so random is random. The best way to avoid ifritites is to mass murder crap that's baseline EP, as far as I can tell, they don't drop avatarites.

The number one reason flame geodes are expensive is because of pyrosoul rings, and more accurately the gem crafted from flame geodes. Because both the ring and the gem are around 3 mil these days. And those rings are expensive since everyone is bandwagoning Resolution/Shoha/Stardiver etc. So, unless the drop rate somehow exceedes demand, the price will never drop on them. But at least if the drop rate didn't suck, people could actually attempt it and make progress.