1997
MS crashes into JV to protect his CS on the last race of the season like it has been done several times before by other people without any trouble.
Punishment: All points of the year taken away and called cheat.
2002
MS made a team order switch with no rule prohibiting it and in a fight for championship.
Punishment 1Million dollar and everybody calling him big cheat.
2003
Alonso brake tests Coulthard during Nürburgring race at over 300km/h causing DC to crash out heavily.
Punishment: no punishment for Alonso.
2006
MS stops in Monaco to avoid crashing into the barriers. There is no evidence or prove that it was done on purpose. There is no rule covering such a incident and deleting his fastest lap would be enough to give the advantage back to the other drivers.
Punishment: All lap times deleted -starting at the back of the field on a track like Monaco and really every idiot calls him biggest cheat ever.
2007
Alonso blackmailed his team McLaren Mercedes. Proved by the quotes of Ron Denis. This is not just a race incident but also a criminal act in civil live.
Punishment: none for Alonso.
2008
Alonso asks his team-mate Pique to crash his car on purpose. Its quite possible that he blackmailed his team again with his contract and the Sponsors.
Punishment: no punishment for Alonso (he even can keep his points), Piques career is over, Briatore gets livelong ban.
2010
MS mad a super overtaking move against Alonso in Monaco. The rule was unclear and mistakes where made by FIA/race control.
Punishment: All points taken away and everybody calling him big cheat.
2010
Alonso makes team order switch with a clear rule not allowing it. Furthermore he is not really fighting for championship. Notice it’s the only incident where there is a absolutely clear rule that prohibits exactly this situation and they are proven guilty.
Punishment: no punishment for Alonso, team pays 100.000 dollar but probably gets the money back with got championship position in the end of the year.
2010
Schumacher defends position against Barrichelo, but let enough space for his car so no crash happened. So normal driving and there is no rule against it.
Punishment: 10 places refined and everybody calls him dangerous driver.
2010
Vettel loses control during Spa race causing a unwanted crash where his own car and the one of Button gets damaged. In fact a normal race incident so you would not expect a punishment at all.
Punishment: 10 seconds drive trough.
I am sure you can find more examples, thats just what came in my mind in seconds. It becomes clear that Alonso gets his own very mild judgement. Usually he is treated as inocent, some might even call him the victim.
Yea bad Massa let him pass by so that everybody can blame Alonso a cheat.
This Massa must be a very bad person, almost as bad as this Pique.