I am so sorry for the long post but I think this may help (I hope).
Bold: I think the question would've been better phrased as something similar to this -
"There is an activity (which my son can do at any time) at my son's nursery which I don't want him to do. I have raised my concerns with the nursery but they will continue to allow the activity to be done by the children as this activity is limited to 5mins (due to popularity). I am still unhappy with this but would welcome your views on how to handle the situation."
I think you are generally voicing a concern about any activity which a parent might disagree with (due to their own beliefs/religion/experiences/etc) but the nursery (and maybe society in general) think is ok.
Another example of an activity where people might not want in their nursery is the watching of tv. I know parents who don't have tv so they feel as strongly as you when they are told their child has 'watched X program' despite it's educational value.
Bold: In answer to your question.
As other posters have said. There are some activities in a nursery (schools, universities, etc) environment which we may disagree with but decide that these are not as important as the other aspects of the programs/facilities offered and therefore continue to allow our DC to go there. You mentioned earlier that Monisory nurseries often don't have computers but you chose not to go there due to other reasons.
I guess you have to think /put yourself in the shoes of the nursery staff. How are they going to monitor your son? If you demand that he doesn't use the 'activity' how is he going to feel? How would they stop him from doing that 'activity'? How would stopping him affect the other children?
I would like to point out that pc's in schools, nurseries, etc are 'closed environments' i.e. rarely open to the internet and have limited programs which have been approved by several committies/government bodies/etc.
I think if you are still concerned can I suggest that you ask what programs the children have available. That way you could view/play these to see what the educational component is. If you still think one is detremental in any way you could then explain this and they may pass on your concerns to the selection groups even if they don't change the program to another more suitable one (in your view).
Generally a nursery has a set program of
- children arriving and settling in
- breakfast (if they arrive that early)
- scheduled activities (usually stories, interactive group things)
- snack time
- scheduled activities (usually stories, interactive group things)
- outside play
- lunch time
- scheduled activities (usually stories, interactive group things)
- outside play (some do several activities outside depending on weather, etc)
- snack time
- scheduled activities (usually stories, interactive group things)
- parent picking up kids
- evening meal (if they stay that long)
Usually the few minutes between schedule acitivities and/or meal breaks the children have free play.
For example if your son is a quick eater he may finishh before the others so the staff may allow him to quietly play at an activity he chooses. if he chooses the computer so be it as long as he is quiet. This is obviously limited as children may finish before him and be on the pc so he cant use it so he chooses another activity.
Overall, I do think the nursery staff would be correct in their belief that your son would have only a minimal time to use a computer.