OK. For relaives or known friends it is no problem.
For someone not known but is known through some other friend or relative the decision can be made on individual basis. How much time or resources one can afford and for how long. These guests must check before coming to tour and try to stay as guest.
Many times these touring people are just passing through the area and with limited budget only require short stay. In that case its OK to have them.
These people do need help and try to bring gifts or some token of appreciation based on their abilities not that it should make any big difference.
And “users” are there no doubt but fortunately not many. 
I think it goes both ways. When someone goes back and tour Pakistan they may stay at someone’s house as well. Mostly to relatives or good friends.
Oh I might add: Those who live abroad may feel even their good relatives/friends as being burden and forget that in past same relatives or friends helped them in their younger days or they had spent many many happy days together! Then these same FOB’s/FOP’s get mocked at being from village or pind!
In essence: What I think, generalizing FOB/FOP’s or ABCD’s is not the right thing to do.