pretty girls (without money) have access to a wide pool of potential candidates, while a charming boy without cash won't. This is what I see in Eastern Europe. Some towns are also dying because of this (the other reason is availability of jobs ofc)
And also how many international long distance relationships are in the town. Especially compared to how many single guys are there. Given how hard it is to keep long term long distance relationship and additional complication of intercultural one, it is super unlikely that planes are flying there every weekend full of boyfriends.
What confuses me about your post: Why do the girls of your town data guys from abroad but the guys do not date girls from abroad?