Depends on a number of factors...

Time: If it's after about 11am, I'd take the Metro with me and recycle. If it's after about 9.30, I'd take the Standard and recycle since I assume it's less likely someone would want one and not have it at that point.

State of the paper: If it's more or less pristine, I'll leave it. If I've done the crossword or if it's obviously had a few readers and is the worse for wear, I'll recycle.

Destination: If I'm heading home/office, then I know where the nearest recycle things are. If I'm going to a meeting/appointment, I may not so might be more likely to leave it.