Even regardless of the confidentiality aspect (and we all know how Apple feels about that), for a decent number of folks, they might need some decently expensive equipment that wouldn't make sense to buy for everyone individually.
At least according to how I perceive the company, the folks coming from that side of the business really run things, and so they bring the in office culture with them even to the pure software businesses.
Obviously this is a lot of speculation, but it seems like a reasonable way to explain why they are the way they are.