yeah, we had a problem with that at one villas that I managed, they started feeding the monkeys that had not yet seen the human inhabitants as a source of food... once they figured out that these really big ground monkeys (people) are going to hand them slices of pineapple they would wait for the humans.... eventually the actual monkeys lost their patience and just started invading verandas and even learned how to break into sliding glass windows and doors.

It took us a long time to recover from that and sadly, there were some monkey casualties (these hits were not authorized by me but the local Thai staff saw it as the quickest solution and even though it was cruel, it did the job)