I have definitely brought back 5+ bottles of various things accumulated in a trip - never experienced any actual breakage, but I did have a weird NZ pull cap come off a beer bottle once, volume was low enough it was just my belongings that got drenched.
I also remember picking up my then 18 y.o. brother from YVR and he REEKED of rum because one of his 5 bottles of rum shattered. No one at customs blinked when he declared nothing.