One of the big strategy consultancies has published a private paper focussing on turning call centres into profit centres or, at least, revenue generators. All very sensible, of course, and something that can offer multiple benefits. The key I'd suggest is obtaining permission to talk to the customers and ensuring that your "intrusion" into their lives does not denude the quality of service they're receiving.
For example, a state government with which I was consulting some years ago had a shiny new call centre for citizens' enquiries and a lot of over-capacity. Turning it into the host of a two way conversation with citizens allowed new initiatives to be publicised, enabled satisfaction research to be conducted in-house at a considerable cost-saving and also energised the call-centre staff.
By contrast, I have recently been trying to re-activate the online element of an airline bonus scheme. While the staff have been unerringly efficient and helpful, every call has suddenly been punctuated with two questions asking me whether I am aware that they are a full service provider scheme and if I know of their partner participants from whom I can also collect bonus points.
There is no context for these questions, they are irrelevant to my enquiry and take up my time, but the call centre staff are clearly obliged to ask them and do so in a monotone that contrasts with the rest of our conversation. My answers to the questions (and I imagine those of many others) have little bearing to the truth but rather are designed to get me away from this intrusive survey and back to my enquiry as soon as possible. The outcome? Dubious market research results, depersonalised call centre staff and irritated customers.
By all mean leverage your asset, but never, never over-ride the original raison d'etre of the call centre. It is a cost centre for a very good reason. Your customer!