"Monks" includes everybody?
It is an effect by wrong way commentary reading of the western professors and thai professors, because they have not enough skill to read pāli tipitaka and commentary.

Commentary just want to said:


  Buddha called "bhikkhave" because the listeners in front of buddha are bhikkhu. But it doesn't means the other buddhist people can not practice follow that sutta.


But in the appearing commentary doesn't said  "because the listeners in front of buddha are bhikkhu", like above, because it is simple in mukkhapātha tradition to call just the specify target, most cases are the nearest. And the most buddha's nearest people were bhikkhu.

Today, you can see in the classroom, when the teacher ask someone to teach 
, such as "Peter! don't break the school's rule", it doesn't means "just that one can't break", but it means "everyone in school can't break". It is simple, so it doesn't need to explain as "the others can't break, too."

There are some excepted cases that should use the difference meaning of "bhikkhave", such as in 1st vinaya rule. For those, there had the explanation in commentary, case by case. It does't means "commentary commented by there own opinion", but it means "that sutta's context or the other related sutta make the commentary commented like that". Because the commentary teacher must be tipitaka memorizer in ancient theravāda tradition, such as ancient mahāvihāra monastery. 

I don't want to blame the others, but I must specify an actual main problem cause of new age buddhist students, that make them feel so hard to study buddha's teaching.