Making work easier for terrace waiters

We have seen an idea that seems interesting to us on social networks, when we are on a terrace and get up to leave the chair resting on the table so that the waiter knows that he must disinfect that chair and that table.

In this way, the waiters will be able to differentiate which tables have been used and which have not been used with a quick glance.

What do you think of the idea? All to facilitate the work of our hoteliers in returning to the new normal.