There's certainly no harm in having a lock but if someone wants it, they'll find a way to get it, lock or not. Of course, I am a believer in "make it difficult for them to steal"... so I lock my propane tanks, bikes, batteries, doors, etc.
Mike, Sue, Sissy and Little Man
2015 Ford F350 Lariat FX4 6.7 CC DRW
2015 Eagle Premier 351RSTS