How would you feel if the terms of the bounty campaign were changed?

So I am a bit curious about how you would feel if the terms of a bounty campaign you participated in were changed without letting you know (and you only find out via payout message when you receive the payment). Before this bounty campaign I had only participated in one (currently participating, so I haven't been "paid" yet) but I would like to know if it is common practice to change the terms without notifying participants.

(Not sure if I am in the correct topic, so please let me know if I need to move this post).

I participated on a creative bounty that encouraged participants to do a "clever, fun or interesting interpretation" of their project, using their logo. They encouraged participants "to think outside the box and submit photos, artwork, installations and craft as well as images, gifs and videos." and requested unique, original and creative content.

The terms were clear (I copied / pasted their terms here, but used an asterisk to cover the project's name):

"Participants will be paid 1000 - 25 000 into their ****/*****WALLET depending on the creativity and originality of their creation. The more creative, the more ***COIN!
The creative campaign will start Friday, 8th September 2017.

Note: You are not allowed to use our team member's faces in your illustrations. If you are found using our team members faces/pictures, you will be removed from the campaign."

In addition to this you needed a wallet that supported their coin (to receive payment), there was a form to join (here you could submit each work), and a link to the spreadsheet (i am guessing to check if your creation was registered).
After I received payment I noticed the amount didn't make sense, and another member also asked about possible miscalculations or misunderstandings about the campaign on the thread. Their replies were that "we have paid a collective amount for all the illustrations you made, as clearly mentioned on the payout message" and "you were paid a collective amount for all the illustration and not for individual images." However, nowhere in the terms of the bounty did they mention that a collective amount would be granted for the creations.

I assumed that by creation you meant submission (since you had an individual submission form, not a collective one), which is why I submitted my 25 images independently, by filling out the form each time, and not as a collective work. I would understand if not all of them counted for whatever reason, but even if at least 10 – 12 out of the 25 were good enough, I would have expected to be awarded between 1000 – 25000 for each of those creations as the terms read. And, since they also mentioned "The more creative, the more ***COIN!" I would have thought that if 5 of my creations were picked as their team's favorites, that meant they would have received a higher award, but that wasn't the case either. Apparently I got the lowest award possible for the 5 picked as favorites, and that is not how the bounty was advertised.

I have seen other bounty campaigns setting a deadline, or no longer receiving participants because they had a cap. Maybe this is something they should have done before ending the campaign (or setting a max number of creations per participant). Making changes at the end of a bounty campaign is wrong, and in my book it reduces their credibility (it would be like paying a lower number of stakes, or a collective amount they see fit, to Avatar & Signature bounty campaign participants and only letting them know in the payout message). If they change the terms in something so simple, how can investors be sure they won’t change the terms of their ICO as it better suits them, or even worse, scam them? Where is the security? (yes, I know a lot of ICOs are not safe, but this seemed like a strong project).