No, no, no; you misunderstand. I'm not saying that's an evil thing; I'm perfectly happy to say "We'll talk sometime" and let it happen when it happens, and I suspect everybody else is as well. What people are objecting to is SAYING "We'll talk at 3pm" and MEANING "We'll talk sometime". If you don't want to make a plan, the proper way to do that is to not make a plan, instead of making a plan and then thinking later "Well geeze, I gave my word that I'd meet this guy at 3pm but I'd really like to take a walk instead, so maybe I'll show up this evening instead".