Two things:
1) Do you refer to campers as people who sit in dark corner only, or also people with snipers the pick people off at a distance instead of quickscoping and "that sort of camping"?
2) Some of the camping gushes from the maps design. Tiny have less place to run from your enemies and have less resorts and non-populated areas, with the action and enemies being around every corner. With bigger, more open and less cluterred nad clustered map design, there will be less camping. Of course, considering your definition of 'campers'.