Why buy the cow if you can get the milk for free? Unfortunately, there are hobbiests out there that will take up this offer as another patch for their logbook.
Instructors and DMs that teach/lead scuba as a hobby make it hard for professionals to actually (try) make a living. This mentality feeds into the 'unpaid crew' that I see so much in Jupiter and Palm Beach FL. I mean, as a recreational diver, who would not want to dive for free as opposed to paying the $65 charter?
If it works for this dive operation, go for it, but don't expect the majority of PROs to agree with you and certinally dont expect to have top notch talent. I dont know this operation personally, but I bet their reg tech is an intern too- not my gear!