It is true that such a player sometimes will make a play that will result in the dealer beating everybody rather than breaking. However in the short run such a player is just as likely to help you as to hurt you and in the long run they won't make any difference. The cards are in random order and they are not prearranged to make the dealer break assuming correct play. If anyone rebukes you for hitting a stiff hand at third base tell them you'll keep doing so when the odds favor it and if they don't like it they can find another table. A friend of a friend of somebody I know makes out well using a gambling system.
People are much more likely to boast about winning than admit to losing.
The fact is that no system can beat a game of luck in the long run.