I'd say that
1.) This has nothing to do with Groupon. Groupon is an advertising platform, just like radio, TV, newspaper, etc. Whether Groupon would be a good idea for one particular business is up to that particular business owner; I know it has been pretty good for me.
2.) This has everything to do with the dive shop owner/operator. They are the one(s) responsible for ensuring their students are well trained, ensuring they don't have a negative impact on the environments they train their students in, etc. If they don't care about both of those things, they won't be in business long.
3.) The mentality "dive training just ain't what it used to be" is in my experience, a bunch of malarky. Intro courses to something like SCUBA in my opinion SHOULD be as accessible as possible. Again, it's up to the owner/operator to ensure they are train their students to the minimum standards set. If OW classes were Navy SEAL training exercises, we'd have no dive shops to fill our tanks, because there wouldn't be new folks joining the sport/paying for new gear and training. Don't get me wrong --- safety is #1, and I think dive shops should only allow OW card holders to go on chartered dives less than 50' and calm conditions. But there is not a high incidence of new diver fatalities (this is an assumption: it seems to me most diver fatalities are advanced divers/cave/wreck etc), so that would indicate that beginner-level training is sufficient. Some of us wanted to get our DM and all the merit badges, some folks just want to be able to go down 30' and safely explore the coral and fishies.