I play on real hardware and I find myself using emulation. You can argue all you want about programmers deserving compensation for their work and I'll absolutely agree with that, but this is a gimmick emulator for nearly 40 year old hardware the creator had no involvement in other than giving it a fairly nifty look when you play. Going from commercial product to open source is a cause of celebration in programming circles, but the other way around is (understandably) much more frowned upon - why take something that used to be easily glimmed through and allowed people to fork over and make it harder to contribute to just for the sake of money? It's not a good look, really. My problem with 3dSen is not that it mucks with how the games are meant to be played (after all, it's only ever an alternative), it's that if I recall it used to be an open source emulator like the majority of them, but the creator decided it would be more worthwhile to commercialize it. which is something that is the default look of the concept of emulating.
Now, some people love this look - I happen to like it most of the time - but a big appeal of retro gaming for a lot of folk is the pixels! The sharp, defined pixels. YoshiM is totally right: not everyone has the time nor energy to go find some old TV, ensure that it's good enough for their uses (or worse, trying to pair period-correct hardware), hook everything up, and accept that if they're using a consumer-grade television with standard RF or composite/RCA hookups that the image quality is going to be distinctively blurry and fuzzy. This is a hobby that demands accessibility or else it will go the way of the dinosaur. How you play your retro games should matter way less than being able to play them. Emulation has come a long way from the days of NESticle and ZSNES. For instance, emulators like Mesen or bsnes provide cycle-accurate emulation to people with reasonably powered computers (basically, anything that isn't a potato), and equivalent emulation for other consoles exist pretty plentifully. I think a lot of you are misinformed on how emulation fares these days, especially compared to real hardware. Both emulation and real hardware have their place.