Is a business responsible if their employee steals from a customer?

The business COULD be responsible if (a) the employee was acting within the scope of his/her employment (probably not the case here) OR (b) the loss was caused, in whole or part, by the business's negligence (for example, if the business had had previous complaints about this employee's honesty but had done nothing about it), which is a tough case to make.  On the other hand, the business may be willing to reimburse you for what you lost, which presumably is not a tremendous sum, in order to avoid the bad publicity from, for example, a yelp review mantioning the theft.