RTG
Well, we all know that RTG allow the individual operators to alter the payouts of the games. With tables and poker it is done by altering the paytables, but with slots it is hard to see what has been done because they don't use proper reelbands as do Microgaming.
I have had over a dozen bonus rounds recently at King Solomons. Most were bad, some were awful. The best paid around 60x bet, but the rest were no more that 25x bet, with many not even making 10x bet, even with retriggers! Worse, the line wins are rarely up to much. I actually came out ahead in the last session, but what is amazing is how LITTLE I won with all those bonus rounds. Would be better to have less, but better ones.
I play bonus slots because of the lure of a decent bonus round, too many like that and I will lose interest. Most other games are not allowed for the various coupons, so if the slots get boring, I may have to play elsewhere, and sod the 75% bonuses.