Almost all LARS are provided by military controllers. The majority of the cost of providing these services is bourn by the RAF/MOD. LARS was originally introduced to provide RAF jets with a means to enter the UK low flying system. Subsequently it is used to keep fast pointy things away from puddle jumpers below 10 000 ft. As I understand it the RAF pays for some civil airfields to give a LARS service where possible. This service is not guarenteed though. It is dependent upon controller workload and if the workload is high then the first thing to go will be the FIS/RIS to a military jet or some C-152.