This all depends on market. Teachers are available at low rates. So, the rate is low. Most of the teachers are fresh graduates and they consider the salary just a pocket money.
Most of them are house wives too who have PG and BEd degrees in hand
The housewives also just seek an opportunity to while away some time outside home. The small amount received is just a pocket money for them also, main earner being husband.
I forget to add one thing....
More than 80% of ladies(+45 not taken in the count) are either graduates or post graduates in Kerala. It's not an astonishing thing here. But their husbands may not be that much educated...may be SSLC or PDC who start earning at an early age before 20. So, they are normal workers and their wives may go to teach in some school nearby. So, husband's money can never be considered as the sole source of expenditure since majority of Kerala men are in the hands of liquor......who spends daily 100 or 200 rupees daily in the liquor shop without any hesitation. So ladies have the responsibility to look after the kids by the way she could.
Since they are educated, they never prefer to go to work in fields or mansion work which can give them minimum 400 rupees per day. Instead they prefer nearby schools which they may get around 3000...nothing else.
Yet, some teachers are also there whose husbands earn big amounts. Yet, it's not the case of all