Yes I know it does that but I do raffles all the time and have come to know that people find it confusing they have to do !currency to check how much they can buy then !ticket amount then do !tokens again to confirm. I have used this for a long time and do 4+ raffles a day and an auto confirmation would eliminate the confusion.
The general population that watches twitch wants everything spoon fed to them pretty much. I have been forced to just do keyword raffles because people find it to confusing even with a detailed overlay explaining how to do it which you can see on the imgur page.
http://imgur.com/PzmHgDMThis is coming from a full time streamer who has 300+ viewers average.
An Alternative would be if the max ticket amount is set to 25 and a user has 22 and if they do !ticket 25 it would buy 22 because then I could just say to enter type: !ticket 25 . But currently It will not purchase any tickets though unless they have equal or more tokens than the !ticket command they did.