Well, it looks like spamming user generated video sites is a sign that online video is here to stay. Even though the main industry players aren't concerned about it, however, their reasons are somewhat flawed. In other words, there are ways to benefit from spamming video sites even though spammers can't make money from users viewing their videos yet.

First, the Wall Street Journal reported:

Here's a sure sign online video is growing up: Spam has arrived.
[...]
The simplest form of video spam occurs when users submit clips with misleading lists of keywords to describe them, such as using "Britney Spears" or "World Cup" to label videos that have nothing to do with the pop star or the soccer tournament. The spammers misrepresent their videos in the hope that the clips will be picked up [...]

Then, Search Engine Watch explained why video sites don't see this as a problem:

YouTube and Revver spokespeople each dismissed the effects of such spam as minimal, which is likely true. Right now, there's not as much incentive to do it, since the spammer doesn't stand to make money directly from someone viewing their videos.

Now, that's fine if I want to generate revenue from views, but there's more than one way to crack a nut. What if I just want free advertising? What if I'm looking for publicity much along the same lines as a TV advertiser?

Well, I can create several YouTube accounts, for example, upload my infomerical, and tag it with every popular keyword. The next thing I know, is that 50,000 users have viewed my content over, say, half a dozen channels. If I keep these ads down to 15-30 seconds, moreover, I can pretty much guaranteed that those users will see it through until the end. The end result is that I've spammed YouTube, got the message out there, and it didn't cost me so much as a dime. Hm, I hope that I didn't just open a Pandora's Box.