Pricing is huge. This isn't a professional sport, no matter how we try to act like it, and without the cash flow you see in MLB and NBA, you simply can't run things the same way.
The marketing for high level games starts at the local league, and eventually makes its way up. That's how it has to be due to the lack of cash at the non-existent corporate level. And most leagues don't know how to do it, or don't care. Even the simplest things can make a difference, but not everyone has a background in that industry. There's a lot more I could say about that and often do, but that's not your question.
The last point is that I don't think you're totally right. This sport is growing immensely quickly, faster than leagues can actually keep up with it. That's why my advice and marketing and business management has suddenly made me popular. We're hitting a point where there are enough people that weak foundations are making themselves known. So while it would be nice to sell more tickets, things are moving. It's not like this sport is stagnant or shrinking.
The other thing is perspective. I don't really watch sports, but I went to a Giant's game once to say I did. It may have been the most boring hours of my life. And most of the seats were empty. Because even major league games don't get that great of traction until it's the end of the World Series. They don't care, really, since sponsors cover the costs anyway. You wouldn't know it was empty from the footage, because they only showed close ups of the parts of the stands that had people looking excited, not the empty seats or the people playing on their phones.
Lastly, look up the last game at champs last year. I was there, with a near the front edge seat, which was an amazing view. But I didn't see the crowd filtering in until the end. That stadium was packed with hordes of screaming fans, locals who wanted to support their team and friends of fans. The intensity coming off of that crowd was like nothing I'd ever experienced before. The other games weren't as insanely packed, but there was never a game I thought looked empty. It was in line with other sports. Maybe early morning ones, but that's normal. So I suspect that it isn't quite as in need of growth as one might think. The idea that this is an obscure game that'll never be taken seriously in the mainstream is on the way out, if not gone completely (it definitely is in Portland).