So I've started ripping my first sprite sheet, and my gut instinct was to use a checkerboard pattern for the background to keep the sprites aligned as they would be by the system (in multiples of 8 pixels) to make animating easier for anyone who would be using them, so they don't have to manually align anything. Then I browsed around a lot of games on here and noticed that I couldn't find a single sprite sheet that does that, and almost all of them are just thrown on a single solid color background. Is there a reason for this other than "it takes too much time"? I just want to make sure I'm making it easier for whoever is consuming these sprite sheets, but maybe this will make it more difficult, or there's something I'm not aware of. 
(Edit: I've also noticed there aren't many transparent PNGs and most people choose a background color instead. Is there also a reason for this standard?)
(Edit: I've also noticed there aren't many transparent PNGs and most people choose a background color instead. Is there also a reason for this standard?)