Casinos typically can adjust their payout rates in three categories of games:
*slot machines as slot machines
*video pokers
*table games
Both the video pokers and table games can be adjusted by changing the video poker paytables or the table game rules (number of decks in blackjack, surrender, stuff like that.) In software by the bigger companies, the video pokers and table games act like they do on land--with behavior true to the performance of cards.
Not all gambling software will do this. Gambling Federation
aka iCrystal software specializes in video poker...and does not appear to yield Royal Flushes to players who are not webmasters. Casinobar's software is non-random with respect to blackack and roulette.
Microgaming casinos can change the rules for their blackack. However, the basic strategy in their Viper autoplay is a "one size fits all", so it is not optimal play for that casino's rule set. Players should compare the BS to the appropriate one at the Wizard's site and tweak it.