That sounds like a guild problem, my guild requires everyone signup up and participate. If you happen to have a reason you can’t then we have the members assign everything worthwhile to defense.
My guild is a mix of FTP and PTP and we sit around 540M GP. Our last 5 losses:
1 - Guild has 620GP only signed up 503GP and has 49/49 for almost every GL, the lowest was 46/49 on GL Ahsoka
2 - Guild has 655GP only signed up 510 and has 50/50 for every GL.
3 - Guild has 619GP only signed up 502 and has about 49/50 for almost every GL. GL Ahsoka is at 40/50
4 - Guild has 615GP only signed up 507 and has 50/50 for most GLs. GL Ahsoka is at 41/50
5 - Guild has 601GP only signed up 390 and has 48/50 for most GLs. GL Ahsoka is at 31/50
Going against these powerhouses when their leadership “Choses to only allow some to signup” sucks. There isn’t anything a guild like mine can do on defense or offense to counter a guild that leaves an entire wall of GL Ahsokas.
There is no punishment or reason for these guild to fully participate since they only need to have 380GP signup to get the highest tier box. If the reward boxes get re-worked with higher payouts then the issue would go away overnight.