I won't put words in bigboreblr's mouth, he may have info to add. But a lot of plantings done are to meet contract requirements ($) or done by DNR types that don't follow up with watering/weeding needs. Tubes are not magic, but do encourage more rapid vertical growth. Neglected plantings obviously fail at a higher rate, so success depends on the investment made after planting, whether started in a tube or cage.
As this thread points out, there are a lot of ways to get to a positive result. The thing these strategies have in common is that they are put into practice by people with enough interest in success that they hang out on a Habitat forum. The folks here are undoubtedly much higher performers than the average Joe...