They know they will average 175 at best on the harder stuff so they don't bowl.  Mike L summed it up well.  But what they don't realize is that the more entries there are, the lower the avg to min-cash will be.  If you look at the "normal" top 5, there is no way +130 would be low to cash if there were, say, 15-20 more entries.  I'm sure the house bowlers look at the scores and say "OMG I can't avg 210 on this, I won't bowl!!1!11!"  

If you want more entries in a tournament, you gotta put down a house shot.  It's just the way it is.


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C.J.