You can point directly to marketing for Dollar Shave Club's success, and nothing more. They emerged at around the same time as things like Amazon's subscription service, which offers the same or even greater value (the selection is much greater), with a company that people are already familiar with. But DSC paid for podcast and TV advertisement, so instead of people going from grocery store to finding their own cheaper alternative, they went straight to DSC.
From a business standpoint it's a great strategy executed at the right time, even if it does feel icky.
Personally I use a stainless steel safety razor for $30 that will last forever, and blades that I got from Amazon at $12 for 100, each lasting about two weeks of every other day shaves as I have fine facial hair. DSC can't beat $12/year.