I don't let my tips mushroom. After a tip is installed, it will usually mushroom depending to the tip hardness, density, general use, etcetera. This method usually keeps it in fine shape. After using the tip until you you see a slight mushroom, stand on the long rail side of the pool table. Place your cue across the table until the tip is just under the far rail. Rub the tip on the cloth under the rail with sweeping strokes while rotating the cue.. Within a few strokes you will see the mushroom get smaller. Be careful not to press too hard because it creates excess heat that could damage the ferrule. Elevating the cue butt keeps the ferrule away from the cloth. This will give your tip a nice finish but probably not better than a pro shop.
I do this to my home table and at the pool hall. It doesn't seem to damage the table. Never had an owner complain.