I know what you're saying, however coming from people who have actually stood there numerous time, as well as planned many of these events in the past, here are my main concerns.
1: People can't even select the correct membership option when renewing. We also had people selecting the wrong amount of tickets they needed for CSS 2012/13, as well as which club they belong to. Other clubs get their own space btw, Clio v6 etc - What makes you think they'll select the correct area they are in?
2: OK we buy stickers, so that's x300 stickers we need to buy, as well as x300 css decals, so that's 600ish tickets in total me and Brian will need to pack up (and IMO it's also an unnecessary cost).
3: What if someone wants to put their car with their friend (which we always get asked for when people arrive)
4: Added level of complexity when creating the ticket packs.
5: People struggle to position their cars correctly as it is, in any order.
Last but not least - We tried it at FCS before and it went to complete s**t because of all the reasons above. CSS is a social event anyway, so people should be able to put their cars with their friends that they convoy in with.
I'm with you on pushing boundaries, but this is an inefficient added layer of complexity and problem causing that isn't worth the effort, put simply.
Anyway, moving on!