I've started to see a memetic backlash to this that points out, quite rightly, that other animal incidents like Cecil the Lion popped up and faded away after a while. The reason for the continued use of Harambe is pretty blatantly an excuse for Internet racists to crack their favorite kind of jokes with plausible deniability. "It's just a [funny/cool/unusual] name," they say, as they continually link Harambe imagery to, for instance, Leslie Jones. The black people + monkey imagery is blatant in most cases. When it's not, it's usually a red flag of the "alt-right."