No consideration

Just want to say one thing -- people have no consideration.  I had people scheduled today at 8:30 pm.  I get home and have an email from them:

We are on our way but running late.  We will be there by 10pm.

Now, that's fine, but... what if I had a 9 pm?  What if I was planning on leaving right after they left my house? 

See, I would be fine if they had even called and said, "hey, we're running late, is it ok if we still head over today, we'll make it there by 10.   Is that ok?  Does that work for you?"  But noooooo, they just assume that I will be perfectly fine with this.  Don't ASK me or anything.

Mind you, these are the same people who wanted to come before I went to work that one day... if you recall, I got up at 5 am, and they never showed. 

Why is it, people would never think to pull this shit with their doctor or with a music lesson, but with the rescue?  Ah they don't care, nothing better to do than sit home and wait for them.......grrrrr.  I need a herd of attack chinchillas for times like these.