This im saying from a personal experience, sometimes the rewards can be so massive and hunters get huge amounts of tokens but the real question is how valuable are these tokens in the long run, the tokens might be many but their value is low, therefore there will be no meaningful returns from them, some might also reward handsomely but again the tokens never gets listed in the exchange platforms. in the long run they just become so useless
The real number that you should look when joining a bounty campaign is how much percentage of the total coins is going to be given to the bounty hunters, there are coins with a huge supply giving millions of coins and everyone is happy but in fact it is a very low amount when you look at the percentage, the most common percentage that I see is 1% but I have seen campaigns giving 3% of the tokens to bounty hunters and that is very good.