Originally posted by: proteeti
Ekalavya really did suffer way more than he needed to.
However, Karna did have his adoptive parents to seek refuge with. Drona did teach him most of the stuff. He was a classmate of the Princes in Drona's gurukul. Drona only refused him the Brahmastra&etc, which in any case he gave only to Arjun and Ashwatthama, which were prizes for being his son, and the most dedicated student respectively.
Karna never showed that dedication to his Guru that Arjuna did (Karna later showed that dedication to Parashurama, so he got those from him).
He did not know his identity right up to the eve of the War. Also, Karna lost to Arjuna multiple times (in Draupadi's swayamvar as well as in the Virat war during Agyaatvaas), so it's not like he didn't get a fair chance.
However Krishna as well as the rest of the warriors always respected him for his charity. His life decisions were always his responsibility.