One Beer is never enough. Where on the site can you see how many "stamps" you have, have trawled it this evening and its not obvious...(to me)
I just called the TO about this as my daughter just buys occasional tickets but doesn't have her own login, just relies on Dad to sort that stuff out, and apparently when you buy a one off ticket you'll get an email telling you how many stamps you've got. Obvs wait and see it in action but sounds like it might work