The host creates one digital collection, guests chip in by card from a link, before or at the shower, and everyone can see the total. It replaces the checks tucked into cards and the cash envelope at the door with one clean, visible record.
Wedding showers collect money in every form at once: checks tucked into cards, cash in envelopes, a Zelle from the aunt who couldn't make it, three Venmos to the wrong host. Someone, usually the maid of honor or the host, ends up reconciling it all at a kitchen table, hoping the total matches the guest list and that nobody's contribution got lost in a card that went home in the wrong bag.
The other half of shower money is the hosting itself, the venue, the food, the decorations, usually fronted by whoever booked first and squared up loosely among the bridesmaids. Run it as its own table: each host chips in her share upfront, costs come out on the record, and nobody discovers at the end that one bridesmaid quietly paid for twice as much as the others. Same clean structure as the bachelorette trip money.
Whoever organizes holds the money directly, it arrives, and TableCash is the record everyone involved can see. Guests who bring a card with cash anyway can still do that; the host records it so the total stays whole.
Someone always volunteers to host the shower and then eats the venue, the food, and the decor while everyone means to pay them back. Fix it first. Each person saves a card and promises their share now, with no charge yet.
No card runs until enough people are in for the shower to happen, then every card charges at once, so nobody fronts the day and nobody can silently disappear. While the table is filling a person can take their promise back with no card touched, and it locks once it fills. This is how you get everyone committed before you reserve anything.