Client books Studio A for two hours, shows up with eight people when they paid for three. You priced for three. You smile and eat the difference.
Someone runs forty-five minutes over. Their card details vanished the second Shopify finished checkout, so there's nothing to charge. You're chasing the money that night and hoping they're honest.
A client emails asking if Studio B is free Saturday afternoon. You're checking a second calendar tab, or worse, going from memory. Get it wrong and two crews show up for the same room.
None of this is a you problem. It's what happens when tools built for selling t-shirts and booking dentist visits get asked to run a photo studio.