I'll admit to having done this. I've never taken "prime" real estate... but I've saved two chairs in the shade for my family of 4 as long as we would be returning in a timely manner (30-minutes or so). Rules are rules... you can't complain about people bending/breaking some and not others... i'm sure everyone here ALWAYS discards their FP once their time runs out... or has never made two ADR's with intention of picking the one that fits them best... or have ever used Disney transportation even when they weren't staying onsite.