I work for Greggs (UK company, sells sandwiches, cream cakes, and pasties of varying temperatures), and we’re required to wear no makeup or jewellery and to keep our hair back at all times. It’s up to the store managers to enforce this, and so the adherance to policy varies from branch to branch. You might just have a relaxed manager.
The ‘no earrings, etc’ rule is either part of Health and Safety regulations or something that all employers stipulate. I’d cite, but I cannot for the life of me seem to find the perfect Google.