If it is an information airfield then of course there is no Air Traffic Control officer, and no clearances can be given so it is not appropriate to request one. However when you announce your intention to taxi, you are likely to be given pertinent information like "No known traffic to affect", or details of any traffic the radio operator thinks is likely to conflict with your intentions. He/she can give you good advice, but cannot clear you as they do not assume responsibility for ground movement or separation in the air: that is your responsibility until, for example, you enter controlled airspace, or get a higher level radar service.