I am Facebook friends with many cake shops.
One of them just put on Facebook "I am closing the shop at 1 today"
Of course, it's entirely up to them what time they open and close, but what cake shop shuts up shop at 1 oclock on a Saturday afternoon ??

If it's a small independent shop then maybe they had a wedding or some other family event to go to. I would have thought most trade is during the week with local workers buying sandwiches and pasties.

They are a cake maker. They don't sell sandwiches or pasties etc
They also shut at 4.30 on weekdays and don't open at all on Sundays.

Loads of reasons:

Ran out of stock
Family emergency
Large event to get to
Ovens/fridges stopped working
Environmental health inspectors came round and shut up shop
Owner wanted to get out of the bakery/shop and enjoy some time in the sunshine.

Whilst it might not be great for business, it's the shop owner's decision to open/close as they wish.

For a small business I don't think thats particularly unusual, if something came up.