the host sends the bill for the month (at us in Ukraine so usually) — so that the client may not know about the need to pay. If coming to the end of the paid period, then the Manager tries to call the client and find out what was the reason for the delay. If the customer answers the call and promises to pay (verbally), then a week the server is running. Then just shutdown and a month later the removal of all information (client can get its data back during this time, but it is a separate service and payment).
In General, in good, the client should be forewarned about problems with payment, at least in the last day by phone. But to expect it not to happen, unfortunately. Everyone wants to blame the host in bad faith while they themselves are white and fluffy.