You want to get lots of value out of these players. Since they call so much.
The important thing to remember is that most passive players only
bet with strong hands and I even seen some extremely passive players check down the nuts (best hand). If they show action I would give it up and fold with a nut like hand.
It is extremely important to remember that when they miss they probably will pay off the whole entire hand and that makes it worth while. That is why you still want to raise.
I raise AA preflop. I bet the flop turn and river. calling station calls, calls, calls, and then shows down something very silly like a gutshot or a underpair.
Yes, at any time they might improve in a hand like this and beat me. If at any point during a hand like this they shove or raise big that is the caution signal to strongly consider folding.