If you don't get how, say, "Pride" "sounds like a single" and, say again, "Promenade" doesn't, there's no helping you. Singles are simply used to promote albums, like videos and all that other crap. They usually pick the catchier, less offensive, "single-length" songs to maximize potential radio-play.
The single version of "Please" was re-recorded probably both because they thought that the original was incomplete and that the original wasn't radio-friendly enough.
They don't sell many singles in the US anymore, since most people just get the albums or download the songs they want.
Some songs get a lot of airplay without being released as a single. Like "Until the End of the World" (which should've been released as a single instead of "Who's Gonna Ride Your Wild Horses," but whatever).
Kieran McConville said:
I guess singles are a holdover from the days when singles mattered, or something. Really, if you like the band, you get the damn album (if there is an album).
Back in the day, the singles weren't on the album. Check out the Beatles, who released enough non-album tracks to compile two
Past Masters volumes (not to mention that the
1 compilation has exactly zero tracks from some of their biggest albums, like
Sgt. Pepper's or the White Album).
This was to extract more money from fans, of course, but it wasn't so bad since lots of bands actually wrote B-sides that were worth turning the damn thing over. If you're basing your assumptions on the latest round of U2 singles, I can see how you'd hear the "All Because of You (Extended Crap Mix)" and wonder what the point of it all is. Can't help you there, sorry.
But anyway, if nothing else, some singles have very, very good B-sides, and they're fun to collect. The Beatles had "She's A Woman," "I'm Down," "Rain," "We Can Work It Out," and "Penny Lane," for instance. U2's "If God Will Send His Angels" single is a favorite of mine because of its wonderful flow (and wonderfully downer mood).
