Yes - seem twitter is so easy to spam - and that makes it a complete mess.
I noticed that Kenyan twitter trends often don't match the content you think they would. There so much spamming, soliciting and abuse of those trends that half the time you have no idea why anything is trending.
Though I don't see the same problem with trends in the US. They tend to be more or less respected. Twitter is probably more focused on enforcing its rules on American trendlines. In the Kenyan space, you can see a trend about say "Raila", dominated by people selling furniture, bed-sitters, just all manner of stuff unconnected to "Raila".