Those are not universal terms, and are actually defined in the contract which you seem to have not read. Grace periods, minimum commitments, subscription lengths, and/or post-paid terms are all common.

Ironically there are far more complaints about cloud providers shutting down entire business operations because of a late payment here on HN. Perhaps you should consider this more thoroughly instead of escalating a single unfortunate anecdote into a strawman argument against how business billing works.