Taking cash doesn’t necessarily mean that they don’t have an account for the club.
As other posters have said, clubs are dependant on the volunteers who take everything on and how they can or are willing to operate
Clubs and societies generally have a treasurers account, I had one for a team until charges were introduced
(We ran some events and wanted an account to hold team funds between making money at an event and overspending on props for the next event, plus somewhere for members who wanted to put some money aside for the next time we played etc - that meant a need to account for what was team money and what was an individuals money. As we had the cheapest free account with just a cheque book it meant that to withdraw it had to be in the bank or transfered to a personal account to enable going to a cash point
We could upgrade, but would have incurred fees so it was good enough for our use, then when the free option was withdrawn we closed it down - we didn’t bother shooing around for alternatives as we don’t run events anymore)
A children’s club may still be able to have a free account depending on the bank and criteria for ‘community societies’ etc
Volunteers turning up each time may not have easy access to the account as it would need to be managed by a treasurer, though multiple names could be granted access - they also may be able to have any volunteer fill in a deposit form and pay in via the counter or deposit point
To take funds in any way other than a pay as you go basis each day does mean that someone would need to track who paid and when - which (and should) could be combined into the treasurers accounting, but they may not be there on the day
Cash, card and bank transfer all have their benefits and disadvantages, and causes enough discussion when a shop etc states a preference
Change can be a pain, the volunteers therefore need a cash float of £1s to change £5 notes down. That means they have to get the cash either from the club funds or personal wallets
A natural form of change could occur if some people bring £1s and some bring £5s or £10s which may or may not be balanced out on the day
As it’s a regular club, many attendees should be able to be prepared with £1s, and then some £5s or £10s may be able to get change
These days card machines are cheap, or may not even be needed with some phones being able to take payment - but they cost in fees
(for the last time I too a £3 payment SumUp took 8p, which is higher than the advertised 1.69% but they round up and charge some card types at different rates)
This is only an option if the treasurer and/or volunteers have the equipment and set up a card processing account - ‘staff accounts’ can be created to take payment that don’t give full access to the account, if the treasurer knows how and if they don’t have a card machine the master account has to log onto the volunteer / staff phone to enable phone payments