EvilDave, we're taking roughly the same approach. Marking is all done off chain, microtrusted instant transactions. We're looking at thermal printed wristbands currently, qr/bar/custom coded, scan to load up with marks, scan at checkouts to pay for things, mobile apps to augment the experience to mark acts/artists, transfer marks between people you meet, tip staff etc. Also considering temporary branded tattoo's for such events, nobody can steal a tattoo on your arm.
The simplest, fastest, most cost effective approach is ideal.
Many other uses have been considered, for instance live beer score boards, based on marks received, or number bought, or both. This opens up more things like betting on which will win. Carry this on to acts, live voting on acts showing at the same time, feedback walls, marking the staff and volunteers at events. All of these are "nice to haves", the basic load and pay use cases are the most critical first. Crypto-Currency has the advantage of being re-usable, instant, cheaper to account and can't be stolen like physical tokens.
Finally, thank you for the compliment, but there are many other people also driving project bitmark forward, with or without my input. It's a team effort, a team anybody is welcome to be a part of.
EvilDave - all the events are in NL - and we have contacts at the major NL music events, and worldwide through the music side (ADE, tomorrowland, ultra) they are watching real world festival progress closely and adopting marking online already.