It's not entirely untrue to say that teabags are "swept off the floor", though it may be misleading. Typically, ALL tea is sorted on the factory floor. http://www.discoveringtea.com/2011/06/21/in-amgoorie-the-fac... However, it is true that the tea in most teabags is "dust" or "fannings": very small broken pieces of tea leaves that remain after the higher grades are sorted out. https://en.wikipedia.org/wiki/Fannings

While a few companies like Mighty Leaf do offer higher quality, whole-leaf tea in bags (or rather, sachets), at that point you're paying as much as a 2x-3x premium over loose-leaf tea of comparable quality. For example, this tea from Adagio is about 16¢ per cup loose-leaf, but 40¢ per bag: http://www.adagio.com/black/ceylon_sonata.html

I'd suggest anyone who likes tea get a stainless steel mesh infuser (they're about $10) and go loose-leaf. It's worth it.