People who like having paper records of transactions.
I'm not sure what's to like about paper records, which are tedious to keep and prone to errors, but you can always write on paper that you transferred $800 to your husband electronically, just like you would write in your check register.
For what it's worth, I'll suggest to you the system that my wife and I used when we first got married and hadn't yet combined our finances. We each had individual checking accounts where we deposited our paychecks and paid for individual expenses, and we also maintained a joint checking account, from which we paid the rent/mortgage, utilities, food, and whatever else we agreed would be "joint" expenses. Then, each month, we'd each electronically transfer our half of the money into the joint account to cover the joint bills, and from that account, we'd pay the bills. All records were electronic.
This is all proven technology, by the way. It was proven back when we did this, and that would be 1999. All records were electronic and we both had transparency into what was going on in the joint account, who contributed what and what was paid out of it, all automatically. I imagine that this is probably easier today than it was 15 years ago.
Hope this helps save you both some time and effort and errors!