Facebook paid likes are essentially useless. I know a few people who were dumb enough to go to Fiverr and pay for likes. This is the worst of the worst. These types of likes are dead profiles, who will have absolutely no engagement with you at all.
Ideally, if you want to pay for likes, they should be in your target market. However, I CAN see the benefit of building up some social proof by using a low-demand area.... I'm talking like 4 or 5 cents per like. I don't see it helping much, but some customers just feel more comfortable seeing that 500 other people "like" a service. Keep in mind that, above all, your goal should be to translate those "likes" into profit for your business!
Stick with a targeted area.