Wrappers are connected with tax concessions. They are an administrative necessity to ensure that the investments for which tax concessions are granted are used in the way the government intended in return for the tax break.
Providers of wrappers usually charge an annual fee for the administrative service. Providers will also expect to earn dealing or management fees from the investments you hold within the wrapper.
Wrappers are routinely sold sold as investments. They are not. What is actually being offered is an investment ready packaged within a wrapper - in other words a product. The standard warnings on products apply.