The scamming thing shouldn't be a problem. To place a line and a maximum allowable bet, you must have the points to cover it, just like an offer in "loan shark" can't be made without the necessary points. Same with the better, he will not be able to accept the bet without the required points, which will be immediately deducted from his points and paid back double (minus 2%) if he is the bet winner.

I would also like to thank Zab for first making us internet poker players and then internet loan sharks. Internet bookies is the logical progression. Until I post about my next great upgrade idea-- the "Hitman" upgrade.