I wouldn't say that getting likes from fellow cleaners is useless - obviously likes from customers is the goal,.. but aren't your customers more likely to click "like" on a page that already has a few hundred fans than on that has 16,...
I run a FB page for my wife which currently has 3192 likes - 2500 of these were bought & paid for & I know are completely useless,.. but back when her page had less than 100 fans she was really struggling to attract new fans,.. now that it appears successful she's getting new likes & new business all the time!