I agree GG that this is seen as purely a cost issue, especially by the bean counters. What they don't realise is that there are no savings to be made when an engineer is checking the aircraft anyway. And as for the safety aspects.....
A lot of airframe damage that gets picked up on wàlk-arounds can be attributed to unreported incidents caused by aircraft loaders (catering/cargo). They rarely come forward and say that they accidentally dented a nose cowl or scraped a door frame. What happens if a person loading your aircraft causes some minor damage and is too afraid to speak up? An extra layer of safety is now lost.