iTunes is a different format, with iTunes offering their animated/movies in widescreen from the start. Warner Home Video have not switched the DVDs of any animated series to widescreen, when the previous volumes were cropped to full screen.Not necessarily. WB released LOSH, Teen Titans, and The Batman in widescreen on iTunes, even though they're in fullscreen on DVD. So if they ever get around to putting S2 of LOSH on iTunes, chances are it'll be in widescreen.
Only new series been released on DVD, have been available in widescreen, starting with Batman: The Brave and The Bold. Tom and Jerry Tales Season 1 was their last DVD release which was cropped to full screen, which matches the previous DVD volumes.