The position of Stack Exchange is very clear: you vote on the question or the answer, not the person. Period. I have been flagging comments by people who say they are downvoting, voting to close or the like "because your other questions...". That's just not right. And these flags have been marked helpful, so the moderators appear to agree with me.
There have been some very silly and useless questions posted here - gold bars, bulletproof vests, and so on - but there have also been some intriguing and interesting ones from the same user, often phrased in a way that is a little irritating, but still interesting. What we should do is clearly to downvote bad questions, close offtopic questions, answer questions we can answer, and edit both questions and answers to ensure they meet our standards around readability, politeness, and so on.
Where this approach struggles is the Hot Questions List. Questions with titles that grab attention bring people over to the site who don't know our norms, and can upvote because of the association bonus but can't downvote. They often upvote the question for being intriguing, and then wander away. I totally agree that this is a problem. It results in a front page that misrepresents what this site really is. However, the solution for that is not to try to get people to stop asking intriguing questions that might attract clueless upvoters. Try to convince yourself that they are also attracting good new Travel users who look at other questions on the site, benefit from them, and maybe even start participating.
Rule 1 on any online community is that it's nearly impossible to ask anyone to stop doing anything. Your best bet is always to ask everyone else to do more of what you want the community to be doing. Here we also have the editing and closing powers to mitigate the worst silly questions. There's no reason to run around doing anything to non silly questions just because you distrust the reasons they were asked. Judge them on their merits, or lack of merits, improve them if you can, and that's all.