Based on this the event at least includes beer, wine and some food before the show
"Each Saturday night, Disney's Animal Kingdom will host a special event including appetizers, beer and wine, along with a new theatrical show in the new Harambe Theater. Afterwards, more food and drink will be on offer at the Harambe Nights Street party."
It's not clear whether the food and drinks on "offer" during the street party is free or for an additional charge.
The other thing that isn't clear is what the show is. If it's nothing more than the free show available during the day it's a bad deal. If it's a new, more elaborate show it could be less of a bad deal. La Nouba tickets go for what $60? $70? for the cheap seats. I guess you could assume $70 for the show/party and $50 for food and drink. Still seems a little steep, but it's WDW so not that surprising.