I hope you ignore Bones's post, Pinbuster...another one filled with negativity...
To actually answer your question, this is why centers start their mini leagues at any time OTHER than when the full season leagues are starting. Most full season leagues start in late August/early September, so start your mini leagues in October. If you want, try them again in November, and December, and so on. Don't start them just to start them, but ask open bowlers if they would be interested in mini-leagues. It is an art. A good salesperson can acheive this without "hasseling" the open bowlers.
As far as increasing lineage, I think that is old-school thinking to do that simply because the league doesn't bowl as many weeks. In my opinion, you should charge more for any league that bowls prime time (6pm or 7pm leagues), and you should charge less for your 2nd shift leagues, regardless of how many weeks they bowl. Perhaps you will charge up to .50 more for your mini leagues, but nothing outrageous.
If you get a new job that is 50 miles closer to home, does the gas station charge you more for the gas since it is losing sales to you? Hell no it doesn't! The only reason you might charge less to a full season league is because they have been there for longer and it is a type of reward to them for coming back every year. These mini league bowlers may never bowl a league again!
I hope this helps you out.
--------------------
Brian
MichiganBowling.com
http://www.MichiganBowling.comFamous Last Words of a Pot Bowler--"Ok, but this is my last game!"