If you watched ads everyday for 20 days, you would get 100 coins. It takes 1 month to get enough coins for a single emblem. This quite honestly is few coins for your time.
If the number of coins you received was increased to 2 coins, it would cut the time spent watching ads in half.
Or, if the number of ads you watch in a day was increased, you could get the same number of coins by watching the same number ads, but you get them in a smaller time frame.
Either of these I believe would increase player engagement with ads as there would be a feasible time frame to earning a reasonable amount of coins.
