Everyone has an evil clone, remember TFP?
If you count parallel universes...or if that even counts as evil.
Those are not clones. Those are
the exact same characters, not copies. They're who and what the characters would be if something about the universe's starting conditions had been slightly different.
They're also not evil - Professor Farnsworth and his alternate self came to that conclusion after extensive study involving the Bible, remember? We didn't see any "evil" universe (which was something of a shame. It would have been nice to have them reference Star Trek's
Mirror, Mirror. Plus, goatees on all of the crew would have been funny).
An
evil clone would be a duplicate created in the same universe, and imbued with some sort of intrinsic property that specifically renders it evil and incapable of good.
As for Lars, remember that he was not a clone - he was a time-travel duplicate. He literally
was Fry, in much the same way as the Frys from various alternative versions of the universe were Fry and yet different than "our" Fry. He was also arguably a good man, rather than an evil one. Just look at how he died.