At my GP surgery they have a tablet to sign in for appointments.
The prompts are
Touch the screen to start
What month were you born? (12 buttons)
What day were you born? (31 buttons)
Are you Winston Smith? (Yes/No)
They seem to have nailed minimal input to sign in.
Since any group is bound to have more than one person with the same birthday, you could combine the sign in process with facial recognition to narrow down the "Are you ..." options and avoid revealing other people's birthdays.
You could even encourage sign-in with some sort of token system, one for each (daily) login to contribute towards a free drink, reduced price Christmas Barbie etc.
In the UK if you store users personal details on a computer you need to comply with various regulations (GDPR). Check whether this is the case for you before starting anything like that.
If they don't want their details on the computer then there is not much you can do.
Then why not use RFID-Chipcards/tokens?...you can get them cheap .. all that is needed is to store a list (in a safe) collecting the info which token belongs to whom on it once...your system does not even need to know the personal data.
For a RPi, I think the interface is USB/serial based.
AFAIK, there are two frequencies, (125kHz or 13,56MHz) ... You'll need to decide for one
You could create two versions/flow ...
recording RFID and allocating it to a name, then store that list in a safe place
recording RDIF incoming/going on your club site.
Edit: My wallbox offers to use these for start charging, where the Wallbox is installed in public places. The "controller" inside is a RPi-3B ... the RFID Kit costs around 30EUR, Reader with 5 Tokens.
USB/Serial use is pretty universal, isn't it?
Your solution would need a case big enough to store the reader, or a more elegant reader with a single desktop case and cable.
Like this (not that elegant, but recognisable, hence).
....then, maybe place the hint that these Cards/Fobs can be individualised (offset printing, like with a theme or logo)...there are special shops out there, that have this on offer
OMG! Is that really how it works? Do they assume that there is one one person with the same birth date registered at the surgery! Or do they throw up a list of names (which would need reporting as that would be a serious Information Governance and patient safety issue!).
I think Andrew may be in Oz? If so, I think their requirements are also quite stringent.
However, some of this will come down to what kind of club is this? Do you have a constitution of some kind? Is there already an agreement for the club to manage a membership list? (Almost certainly there will be).
Yes, this is no different from having a paper sign-in/-out book. Other than a need to keep the thing safe(ish) when not in use.
This stuff is all just detail, all perfectly possible once you have the basics going.
Not unreasonable desire by the club. And a screen with Node-RED would be perfect - AS LONG AS .... the club doesn't suffer from people stealing stuff! You might need to mount the tablet in something large and solid.
Why? Very complex and requires management and admin. The idea of a simple list seems a lot easier.
Trust me, cards/fobs - they will get lost, they need managing, they cost money, they need more managing, they get lost again! Do everyone a favour and keep things simple.
"Just because you can, doesn't mean you should!"
A simple single screen backed by a simple list of members and a reasonably smart input filter so nobody needs to type more than a couple of letters of their name. Ideally with the tablet running in Kiosk mode to stop people messing with it. Send the data to MQTT, InfluxDB or wherever so that you can do the other information stuff elsewhere.
You might need to mount the tablet in something large and solid. 
