People just don't do it often at all, except in response when people try to ban it. The only real effect here is to start divisive argument and polarize opinions. But what everyone refuses to mention is that flag burning could easily be stopped right now, without resorting to Constitutional Amendment, or any other added laws. Most cities have ordinances that prohibit setting fires in public places. Of course, using a misdemeanor charge trivializes the flag issue, which neither side wants.
Demagogues are much happier yelling at each other than actually solving problems.
In my experience, people who believe in alien landings and abductions have no clue how big space is, and how difficult it would be to travel the universe. They're basing their theories on blind faith and Star Trek episodes. Flying all the way around the world, IMO, is about the biggest trip that most people have a decent mental picture of. 25000 miles, it takes a few days by plane, but our fastest rockets can do it in about an hour. From here to the moon is 100 times farther than that.