It's always interesting to me when one persons vision is declared what YouTube is for, no disrespect but I think YouTube is for whatever the reason the person creating or using YouTube wishes it to be.
I think sub4sub is not a smart play, to me it's a waste of time and doesn't get people really viewing who enjoying their work. I bet people who do it find out quickly how useless it is. However, the very nature of having a YouTube channel leans naturally to people to ask other people to watch what they create. How else would others know that they are there?
However, they way on ask makes all the difference. If people have a link in your sig you are asking people to check out your video. People are just being subtle about it. Is that begging?
There are tons of people on YouTube making great money who I think their content is awful. However, I understand that just because I think something is crap doesn't mean it's crap to someone else.
Some folks around here are crushing it and barely get viewed and that doesn't mean their stuff suck. It might mean, again, no one knows about them yet. But I guess they are supposed to chill in a corner and wait for someone to accidentally find their channel and then take off. Good luck with that one. That happen to some people, a very few some people, but it doesn't happen to most talented people.