Ironically, since Spidey isn't in any advertising or marketing, I'm almost wondering if it would have been better to keep him a secret altogether. Think about it. If there were toys and shirts and all this marketing material planned with Spidey included like say...Wonder Woman in BvS then yes, it makes total sense to show him off in the trailer. But if he's going to be absent completely from marketing....maybe it would've been wise to conceal him altogether so that people have a total "OH ****!!!!!" moment when they see the movie. Then again....I guess it would've been spoiled anyway from the early screenings. lol
Don't get me wrong. I LOVED his reveal in the 2nd trailer. I'm just saying.