Carl,
        I worked retail for several years before I came to college
and it would seem that any cash register whcih allows the user to redefine
the keys could be used for this. All you would have to do is assign each
patron type a diffrent key, and then when you closed the register
at the end of the day transfer the number of partons to a form.
I hope this helps in some way.
Tim Daniels
td6560@[log in to unmask]