i would guess it depends on the venue- some shows do not allow a quilt that has been previously shown elsewhere- some allow it as long as *they* have not seen it before,
some encourage you to enter in as many places as you can- but each place to enter a quilt has it's own set of rules-
i don't think it is a bad thing to enter your project in a show, the fair, a lqs offering it---all in the same area- as long as you follow the rules.
i have a number of quilts that have been in shows and entered at the fair.