It is clearly not legal - your former league operator is wrong. Another foul you don't see called much is using your cue stick on the pool table as a measuring device for a bank or kick shot, or any shot for that matter. It's OK as long as you are holding on to your cue, but as soon as you let go of your cue laying on the table, it is a foul. I've seen it called and a knowledgeable referee will uphold that call.
Unfortunately that is not true in all rule sets. It is not a foul to put your stick on the table with out keeping your hand on it in APA, BCAPL and USAPL
For the BCAPL see page 80 in the CSI - BCAPL
1. Situation: Player A lays their cue on the table to help line up a shot, then uses a second cue, a mechanical bridge, or other equipment to assist as well
Ruling: Foul. Only a single cue, held in the hand or not, may be used.
Held in the had OR NOT (means you can lay it down)
It is a foul in the WPA rules