This things happen. vs These things happen.

Some examples from the web:

• Scott and I sort of had this thing happen.
• Michael has gone about making contact with all his inmates in the prison, because every inmate is serving a function for the break, once they do breakout so he needs everyone of these guys to make this thing happen.
• If we're lucky, this thing happens fast.
• Look, no one is saying you meant for this thing to happen.
• Every time he leaves this building, good things happen.
• Look, this sort of thing happens.
• Mother-in-law's memorial is almost here and this kind of thing happens.
• No, I didn't know you'd find out and this thing with you would happen.
• We can't let this Napster thing happen here.
• This is a thing that happens.
• I knew this sort of thing would happen.
• This is how things should happen.
• I fail to see how this sort of thing could happen.
• You knowm the one that... rushed for this whole thing to happen.
• I'm sorry, but things like this happen.
• And within five years, this extraordinary thing began to happen.
• And, I mean, funny things like this happen.
• We in this House insist on three things before this can happen.
• But we cannot allow things like this to happen.
• You see something on it. It's not just to look like a gecko. It has a tail. And just when you think you've figured out nature, this kind of thing happens.

Some examples from the web:

• No, it's just, these things happen.
• You know, like you said, these things happen.
• I'm fine, these things happen.
• No, but these things happen.
• Come on, Paul, these things happen.
• This is a lunatic asylum, these things happen.
• You know was well as I do these things happen.
• I was in the second war, I know these things happen.
• But I figured, it's nothing, these things happen.
• I am sorry; I know you two were close, but these things happen.
• I know it's sad, sweetie, but... but these things happen.
• Don't feel embarrassed. These things happen.
• The whole country is full of people who, when these things happen... ...say "These things happen."
• Now you know how these things happen.
• I don't know what's making all these things happen.
• In 20 years, you might understand why these things happen.
• They were terrorists and these things happen.
• I mean, these things happen.
• It's just... these things happen.
• Belgrade is a big city, these things happen.