Physical Danger
Sometimes gamblers get so upset or, shall we say, festive, that they act irrationally and decide to take out their financial frustrations on you. Thankfully there is a table, a chair, and a burly bouncer named Vinny standing between you and any customer violence.
The greatest risk of physical danger comes from having to toss cards all day. The repetitive motions are not unlike working in a factory—although you're probably not going to get a nail to the face at the casino. You could be standing on your feet for many hours a day. You can develop calluses and joint pain which can hurt like the dickens. Of course, even this tiny danger goes away if you get one of those cushy seated jobs.
That's where the smart dealers work: the casinos that provide chairs.