And as I already mentioned, FW doesn't carry as much consequence as, say, nullsec.
First off, the consequence of losing a FW system don't really hurt all that much. Inconvenient, perhaps, but not exactly something so painful it makes you want to rage quit. Losing a system in nullsec hurts ALOT MORE. In fact, you can even be kicked out of nullsec entirely (as has happened quite a bunch of times), and you can even kick people out of nullsec entirely (also happened a bunch of times). You do not get shite like that going in FW.
Secondly, there's also the lack of perceived solidarity in FW. If you are in Nullsec and you are a Goon, and everybody else who isn't red to you is also a Goon or allies. In FW, even if you guys are all militia, the guy who is blue to you can be somebody else you wouldn't be sharing your lunch with. Loyalists rubbing shoulders with somebody from the other side who is on this side for the sake of profit and will switch over at a moment's notice and etc.
Finally, there's the narrative angle as well. FW is one of those places where the narrative barely changes when anything happens. Losing all of your FW space to the other side? Your faction didn't lose, didn't suffer from economic consequence, didn't lose their minds, nope, nada, nothing. This is at odds with, say, nullsec or w-space where the side which loses actually do lose their assets, get a hit in the corp wallet, get a hit in the cash-flow, actually have their name wiped out of that particular chunk of nullsec/w-space.
Now put yourself in the boots of a third party who is observing the people in FW and the people in Nullsec and then form an impression. Personally, if I were that observer, I will conclude that FW pilots are playing some kind of sandbox freeroam game that only sometimes get together to get something done in the short term, while the guys in Null are playing games of Civ and will collectively lose their shit if somebody comes over to grab a couple of hexes that has all the good moon goo on it.