Although we do not share the same weather as our continental cousins, in the UK many, many food establishments now have some form of external, or pavement seating. Even though it may only be a few seats, this does represent something that should be notified to your shop insurance company.
Any retail business that has a valid policy in force, will have a combination of covers. One of these will be public liability. This is essentially your responsibility, as a business, for injury, illness, disease and/or damage to third party persons or property.
For example if someone is walking along the pavement and they trip over a chair, table, A frame or some other item of furniture, there is a chance that you could face a claim. Whilst it may not seem obvious, you need to check on two things.
Firstly, you need to speak to the local authority (if it is on a pavement or similar) or the shopping centre owners, if applicable, and to ask what is the minimum limit of indemnity they need you to have in place. Many local authorities are now insisting on a limit of £5,000,000, up from the usual £2,000,000.
Secondly, you need to ensure that your business insurance policy notes that you are covered for external seating. Any additional risk factor presented by your business should be notified to them. They may not necessarily charge any extra, but at the end of the day you are better to let them know in the event that any claim is covered.