I am going to take a break from the financial side of life to talk to you about something very important: drugs.
Just kidding, not drugs. Manners.
I am sure if you are x number of years old (where x is equal to or greater than, say... 40), you have contemplated the fact that manners seem to be on the decline. Of course kids these days do not have them, because kids these days are, in most cases, tremendous a-holes. I know this because I work with them all the time. Then again, kids (and I am referring to the somewhere-around-teenage kind, not the diaper kind) are probably always tremendous a-holes during a certain portion of their life. You know, like between the ages of 10 and 24.
Anyway, the problem is that it seems that even people outside the teenage-ish a-hole range are still forgetting their manners, or perhaps they never learned any. For instance, how many times has someone invited themselves to an event you are holding? Or RSVP'ed for themselves and brought another guest (or several other guests) without telling you? Or not RSVP'ed? Of course there are much, much worse social blunders, some downright terrible. But even these little ones are still rude.
But the bad thing about manners is that if you have them, they may get you into an undesirable situation in which you "lose" to a person who does not have them. To whit:
Suppose you have a friend. Let's say this friend's name is Sam. Sam starts dating someone terrible, as friends often do, and because you are older than 13 you know that this is bound to happen. You will doubtlessly see them out and about, and you'll be polite and friendly, because that is what adults do. You might know that the new person is not so good for Sam (because you are clearly much, much smarter than Sam) but Sam is a grown-up and must make independent decisions. As time goes by, this new person inevitably does some obnoxious things, like throws a hissy fit at a restaurant, or starts a bunch of drama at your pub (or perhaps everywhere else), or gets really drunk and breaks things, or sleeps around, or whatever. Sam is still hanging in there, though, because as we've already examined, Sam is kinda dumb. Sam knows you are not fond of this new person, but that you still care about Sam and will let Sam make Sam's own choices.
But then one day you decide to have a couple friends over for dinner. Nothing fancy, maybe you wanna play Scrabble or something. You invite a couple of close friends, and decide to call Sam and extend an invite (after all, Sam has to pick up something from your house anyway). Sam says, well, that sounds great but I was planning on seeing New Person tonight if NP is free. Do you have room for me + 1?
Now Sam has made a social blunder - perhaps without realizing it, but a blunder all the same. It is rude to invite other people to a function. Maybe not as rude as pooping on someone's living room carpet, but still rude. Especially when the "other people" you are inviting are a-holes who cause drama, piss people off, break things, and act obnoxiously. You love Sam, but you have already expressed that you do not love NP, and so it was rude of Sam (not to mention stupid) to invite them to your house and not leave you a delicate way out of it. Sam could have said "Well I was planning on seeing NP tonight if NP is free" and left it at that - then if you wanted to extend the invitation to include a +1, you could, but you could also just say "Oh, well then, have a great time and I'll see you later!" Instead, because Sam temporarily forgot to have manners, you are stuck.
You can either a) say, "Oh, sure, there's lots of room!" and make the people whom you've already invited (and who have already accepted) miserable, not to mention making yourself miserable both during the party and afterward when you are bleaching your entire house and/or cleaning broken glass out of the carpet; or 2) be a giant manner-less bitch and say no. There is no middle ground. There is no polite way to say "Look, you stupid ass, I already told you that you can date whom you like but I don't want to hang out with NP" or "You can come, but don't bring that psychopath with you" or "Sorry, I like my evenings drama-free." It's really too bad, because I probably could have used a polite version of all of the above.
In any case, the end result is Sam w/o manners? Win. You, w/manners? Stuck cooking dinner for an a-hole.
Actually, maybe this is why people have given up manners.
 I would have said 30, which is almost how old I am, but I have a friend who is 38 who is constantly proving me wrong about older people having better manners.
 My *expletiveexpletive* friends do this one all the time.
 Like getting mad if people buy you gifts which are not on your list of demands, or dissing the food you just served them, or not liking your clearly awesome ladybug boots.
 I am sure that you have lots of friends, if you are witty and charming enough to read my blog. But let's just focus, hypothetically, on this one friend for a moment.
 See how clever I am? Sam could be a boy or a girl. I am being very anonymous and respectful here.
 This gender-ambiguous thing is getting a little more cumbersome.
 Or, in this case, permanently