This. And it doesn't necessarily have to be a "bad will" from the power supplier. I know a store who went down because they were relying on a unique supplier

This. And it doesn't necessarily have to be a "bad will" from the power supplier. I know a store who went down because they were relying on a unique supplier and, at one point, the supplier experienced an issue at their factory, outside of their control (a flood). The supplier was big and strong enough to deal with the momentarily slowdown (it lasted months) but the store I knew simply couldn't handle their customers' orders and couldn't accept new customers. It quickly degenerated: unable to pay the salaries, then unable to pay the bills, the tax, etc. And the store, after years of "faithful" services, went bankrupt after a few weeks/months. The sad thing is you could see them trying desperately to stay alive and they were nice people. So it's as you said: be careful to not depend on a power supplier because several things may go wrong.