I know some weedhead Gameboy addict is going for the reply record on this, but I just have to be part of the "fun."
You shouldn't just say stuff like "my mom's cool with it" because it ruins any chance of the fantasy being maintained. There is an outside chance this is true, but that would involve your mom spawning with alien lifeforms to create you and your siblings, then eating the others and feeling badly for you.
If you really want to have "fun," do not stop with free drinks and pizza. Get the guys who come over for their "cut" to offer stolen cars in a nighty bad beat jackpot. Have the cops who come over loan out their sidearms for a little basement target practice at $5 a bullet. Get a couple of girls from your high school to come over, get naked and put on a lesbo show next to the high stakes table. Once a week, spice it up by adding a donkey.
You are on the right track. Don't let anyone talk you out of it. If the cash runs dry, pimp your mom.