I don't think they would only need to pay slightly more. It is a bad move to be entirely dependent on a single customer to the detriment of your other customer relations. To gain exclusivity there would likely need to be a significant premium paid and minimum order commitments.
They're not though. There are still many fabs available, just not the premium ones. It's up to every other company that wants those seats to pony up and do what they need to do to get that capacity.
It's like a restaurant reservation for a very regular "VIP" customer. They may get really special treatment, because they're probably spent enough to earn it. And everyone else schleps in line.
Really there's nothing wrong with that. It may be annoying, but someone is paying way more and consistently for that table.
I think that restaurant analogy is pretty bad. Driving customers to a competitor is a risk you take when locking them out of your restaurant, and those customers could also be lucrative VIP customers as well, not just schleps from the street. If that mega VIP ever stops coming to your restaurant, and you've lost your other VIP/customer base, you'll be hurting big time. This can lead to leverage the mega VIP has over you, as they know you've overcommited to them, and can tighten the screws.
Yet this is what practically all non fast-food restaurants do. And kind of how general strategy goes for many businesses.
I know the few places I frequent often, I get a table mostly right away if anything is available, regular staff knows what I want, more or less, and I get what I expect, mostly because I have a relationship with the vendor.
I tip well. Chat everyone up, etc.
You don't think Apple or TSMC does this?
I've been in that type of relationship in that industry. That's really how it kind of works. It's not even the most $$$$, but relationship and longer term leverage.
Do you reserve the restaurant exclusively for yourself? No. So this scenario is not really similar at all to skipping the line at a restaurant just because you visit often and tip well(which means you are paying a premium here). It's turning away the entire line for a single patron. The restaurant better make sure that's in their best long-term interest before pissing off the other patrons. Also the number of patrons willing to shell out for leading-edge lithography is probably in the single digits. TSMC can't rely on foot traffic to pick up for lost business elsewhere.
