Machines will not be our masters in the sense that they will tell us what to do and what they'll pay us to do it. Machines, after all, do not think.
But we will be their slaves in the sense that we will be constantly servicing them, whether we want to or not.

My point is that the overhead required to maintain a machine civilization is rapidly becoming the bulk of our work, or our expenditures (which is the same thing, money and time and energy are essentially interchangeable). And we are all engaged in this even if we "choose" not to do so. We pay for the internal combustion engine even if we choose not to own an automobile.

The Frankenstein aspect comes not from the consciousness of the machine, but from the changes in our life we have to undergo to accomodate that machine. This is nothing new, we paid a great price for agriculture, but it also greatly reduced our risk of starvation. We receive benefits from our technology as well as the inconvenience required to maintain it. The problem is, do we get to choose whether the benefit is worth the inconvenience? The answer is we don't; not at a personal level (new technologies affect us whether we use them or not) or at a collective level (new technologies propagate through society as if they had a mind of their own, we don't get to vote).

If I want to stay at a hotel, I HAVE to have a credit card for ID purposes, no matter how much "legal tender for all debts public and private" I have in my wallet. If I want to open a bank account, I MUST reveal my Social Security number, even with the risk that the bank will allow it to fall into the hands of criminals and in violation of the laws that once guaranteed the confidentiality of that number. Sure, I can "choose" not to stay in a hotel, or not use banking services, but that isn't much of a choice on a business trip, is it?

We put up with this because the machine needs it. And we have little choice but to deliver.