Completely off the top of my head:
Hamilton: failure to get into Q3 in Australia; spin in Malaysia qualy; overtaking the SC in Valencia; off track excursion in Spa.
Button: failure to get into Q3 at Silverstone; same for Hungary; off track excursion at Shanghai; failure to get out of Q2 Malaysia.
Webber: Bahrain Q3; first collision with Hamilton in Australia; second collision with Hamilton in Australia; losing so many places at the start of Valencia; collision with Heikki in Valencia.
Vettel: collision in Turkey; start at GB; start at Germany; SC in Hungary; collision in Belgium.
Alonso: white line in Oz; jump start in China; FP3 in Monaco; failure to get into Q3 in Turkey; overtaking Kubica in GB; spinning out in Belgium.
Looking at that, I don't think Alonso is significantly worse on this score than the other WDC contenders.
Its quite funny how you include every mistake which didnt even cost a single position for driver, like for example Valencia and Spa for Hamilton. You can make an endless list of mistakes for almost any driver in that way, but whats the point? Alonso has throw away much more points than anybody else by his mistakes this season, twisting things and nit picking every wheel spin from other drivers in cases where they didnt lose anything because their "mistake" isnt going to make Alonso look better.