So, going by the short of the article that snakes should be in enclosures where they can fully stretch in a straight line, the overriding majority of owners both aren't and reasonably can't provide such housing for anything the size of, say, a full-grown boa constrictor upwards. Not only would such an enclosure be incredibly expensive, but fitting an 8 foot+ enclosure (let alone the 15-20 feet of the giants) would be a tall if not impossible order for many dwellings due to sheer space logistics.