Outsourcing non-critical is an essential part of modern industry. Quite a few years back, many factories realised that it is not useful managing the people who took care of keeping the factory premises clean. They outsourced the cleaning job and a large part of the maintenance of the facilities to an agency. More recently, for organisations which work out of offices, and do not have as such as factories, outsource functions like Office Security to agencies.
The core aspect is that every organisation wants focusing on the core part of its business. Even a little need for attention to non-core activities can result in millions of dollars from loss of opportunity. So, outsourcing non-core activities does make business sense.
Similarly, while outsourcing a non-core aspect of the organisation, it is extremely important for the organisation to not absolve from all responsibilities of that function. The organisation should maintain minimum involvement in the outsourced function to be able to have total control over the outsourced activity. The critical decision is how this minimum involvement should be sized?