It's obvious that many of the top petitions were submitted and voted by foreigners. Just from the top 10 most popular petitions as of time of writing this one: Voting fraud in Malaysia; Deport Jasmine Sun to China; Take in Romeikes from Germany; Stop Filipinos from killing Taiwanese; Punish Netherlands for killing Alexander Dolmatov. The vast majority of actual Americans reading the above are scratching their heads asking "who?" or "what?".
The issues submitted by non-Americans may be important to them, but they distract from the issues that are more pressing to Americans. "We the people" want the executive branch of our government to hear our "voice in our government". But right now, the foreign voices are drawing out the voices of Americans'.