PS: You cant purely use margin to compare different type of...

PS: You cant purely use margin to compare different type of business, it has to compare against its peer and in conjunction with various other factors and key indicators
Different industries have different margin due to the business model

what about banks net interest margin between 1-2% ? who the #$@$ invest in that if you think it like that
CBA delivered you 15-20 baggers in its lifetime and then more with the dividend, even with $71 today it far cries from $5.0 float