If you get one them from high rank account your account is dead. You can't learn from it.
I think I misread it the first time, did you mean earn, not learn? Since you mention bounty abuse, I presume you have in mind bounty spammers, right? Always thought they associate themselves with earning and not learning.
Anyway, after mentioning feedback spammers several times, would you be kind and share which DT members have abused their status by giving excessive ratings? Give us a few examples.