I don't think that's a protective measure, to me it just looks like a convenient way of tracking the liquid level in the cartridge. I don't think that a hack li

I don't think that's a protective measure, to me it just looks like a convenient way of tracking the liquid level in the cartridge. I don't think that a hack like this is harming the company or cuts into their revenue - most people wouldn't bother resetting these thing to refill them manually - the labor investment probably isn't worth it. Their target audience would pay for convenience, they already do by opting for cartridges instead of manual addition.