I see your point, it could be used as a way to re-stock their base levels back up again. Give them some breathing space to do it for a week or two, then go back to before. But the thing is, they've posted on forums about doing this for a peaceful solution. So if they change again in a weeks time "for no valid reason", then this time around everyone can see ZA for what they really are.
But you don't know that, and without base access you cannot check their stock levels of fuel to know e.t.c. So even if other Zoner factions suspected that was the case and didn't stop shooting the bases, they cannot prove it and would still come out looking the bad guys. So better other Zoner factions play along for now and see if things do change with ZA in a week or two, I don't see how they have any other option really? Attacking now after what ZA have said and done with the bases, it would only end up making other Zoner factions look at fault.
That's what I think anyhow, other Zoner factions have nothing to lose by saying "OK, we'll play along with you for now, see if you stick to your word or not". If they don't, then back to World War III again. Ha!