The hours shown on the meter mean nothing just provided they are shown on the delivery docket or the invoice.
A lot of mowers just measure the hours the key is on so not uncommon for delivery driver not to turn the key off & run up a lot of hours particularly if it was loaded in the afternoon for delivery the following day
Others measure the hours the engine is running and some with electric PTO's measure the hours the blades are running .
With the latter two one would expect no more than 1 hour if it was brand new or 10-20 if it was a demo off the floor.