Definitely looks like it's been crappy there, but I just pulled the last 182 METARs from KBOI and only 73 of them had FZFG ("only" lol), and looking at the last 24 hours there was a good 6-hour window yesterday late afternoon/evening where it was clear. Seems to be a repeating pattern where it's better at that part of day, unsurprisingly.
So while it's been predominantly crappy, it's not like you'd be stuck there for 8 days. Once you can get out, you can point in any direction to get to better weather and then get going in the direction you want to go, and it looks like better weather in this case exists about as soon as you're off the ground - There's nearly a 10-degree spread by 2000 AGL and it looks like you'd be well in the clear by pattern altitude.
I'm not telling anyone to go in bad weather, but weather is pretty transient most of the time, even when the overarching pattern sucks there are still small changes that can allow for a go if there's a willingness to be very flexible on time.