not recommended buy in, but why not?

OK, the title of this might be a little confusing so i will explain. At my local casino the people who play here are more then a fish, they arent good enough to be called fish. These people are stupid calling stations, now i usually play 4/8 but i never buy in with more then 60-80 dollars. Im thinking about moveing up to 5-10 with a 100$ buy in. Its not correct to do this due to the books but in this situation where i can make a lot of money why not. i was wondering if anyone else does this and is a consistant winner or not.

I think you are forgetting the reason to have such a large bankroll. Its to cover those ups and downs given to you by both cold cards and bad beats. If you sit down with a lower than recommended amount of chips while playing with the worst of players possible theres a chance that your good hands that you play will be beaten by horrible players with horrible cards on horrible draws. It could work out, but you could bust as well.

Its not correct to do this due to the books but in this situation where i can make a lot of money why not.

If you flop the nuts you will not be able to cap all streets. You need to always have at least enough chips in front of you to cap all streets.

What's that typically 15xBB?

12 BB

2 BB preflop
2 BB flop
4 BB turn
4 BB river

When I play 4/8 live, I'll buy in for a rack of $100, then after dropping $20 or so I will get a second rack. The game is so passive and the stacks short enough that a little less than 12BB isn't a big deal.

When I play 3/6 at our local casino. I sit down with $120 - $150, and never buy in for less than $80. Then if I ever fall below $60, I look into what I should do.

12 X BB is enough to cap on every street. It will be if ever that you will do that. But it's nice to have that ability.

I try to have about 20XBB to give me some wiggle room. THis will allow me to play normal poker. And even after seeing a few flops, or chasing a couple of turns, or paying a lot of blinds, I'll still have enough to play a big hand and not run out of money.