Most Signature campaign members are doing this for extra income and a lot of them are not going to have the money to fund a Lightning Network hub. Yes, you might generate a little bit of money, but I doubt if it would be more than the interest you would have received, if you simply deposited that money into a Bank. <The interest rate in some developing countries range from 5% to 10%>
So the question is, would you lock up say $1000 worth of bitcoins in a LN Hub for say a few cents profit a month or get $8 interest on the same amount, when you deposit it into a Bank account at a fixed interest rate.