Here are the best non-slip options for people working in restaurants, nursing, or boating.
Xero Prio All-Day SR - Read my review of them here. Leguano Care (EU) - Designed for healthcare workers. Use code [sc name="mugavik"] for 5% off for retailer Mugavik. Also available in Canada. Birkenstock QO 500 - Non-slip work shoe that is zero drop with insole removed. Barebarics Zoom Astral Loyak - These are boating shoes with a grippy, non-slip sole. Remove the insole to be zero drop and note that they are a narrower option.
The following weren't designed for industry workers, but still might work.
Be Lenka Glide - Be Lenka Barefoot released a new slip-resistant outsole in 2021. Groundies Original Sole - Groundies Barefootwear has 3 different outsoles. Anything made with the original TrueSense sole is slip-resistant (but not non-slip). Bohempia - These are popular among skateboarders, and the slip-resistant outsole can also work for nursing/ food service. Xero Shoes 360 - These are meant to be grippy for quick lateral movement, but can also work in other situations!