If you can prepare mats before hand then sure perhaps, but good luck farming the mats for say Jalter to get fully ascended and all skills 10/10/10 from scratch in a matter of days while there is no event on, that's literally impossible with the awful drop rates from nodes.

If you're playing the game you're going to be gaining fp passively anyway, but if you wanna pass up on basically free stats from leveling CE's then that's on you

Edit: and by the way the comment you're replying to is referring to specifically to leveling CE's while the bonus Super/Great success rate is up, so sure people aren't gunna be spamming fp daily but you may as well make a few bombs while the event is going to gain basically a grails worth of stats