I've been flying in and out of YMMB since 1979 and yes there are a lot of guys/girls that don't maintain 1000'
Just the other day I was driving west along Balcolme road ( west of the Nepean Hwy and 2 nm from the field ) and a new MFS PA28 flew past toward the field at no more than 400' For a couple of seconds I thought he may have had a problem.
the WX was clear blue at about 1700 local time.
I thought about ringing the CFI ( a Man I've known for 30 years ) but decided not to bother..................