Oh no I was definitely thinking "NFT as ticket" here. I didn't mean to imply that no solutions exist -- only that (1) solutions will take some significant custom development (and thus need to be budgeted for), and (2) that (I suspect) something more elegant and easier (perhaps a whole SAAS platform that many can use) is probably out there or coming soon so that many NFT teams may leverage it. In any case, yes, that's a nice approach, of course (thanks for posting, as it's an excellent example of how to guard against some exploits), but it doesn't solve all of the issues mentioned. For example, it requires the user to move the NFT to his/her phone wallet (when they may have purchased at a desktop), it requires the user to have certain apps installed, and it requires the user's phone (which could be any brand/age/OS) to handle correctly. So, you still have to accommodate a lot of various cases, which at scale needs to be planned for--which makes doing one-off systems more of a challenge than, as mentioned, leveraging a full-on service for this. Anyway, thanks a lot for contributing, as your comments will surely give people some valuable direction here! :-)