Credit union customer here. I pay virtually everything by online bill pay if I don't pay cash; this is a free service for us because the paycheck is directly deposited. Usually the only checks (technically a share draft, but it looks like a check and acts like a check) I write each year is to the state and federal income tax, and that's because there's those dratted forms that have to be signed and sent, too. <g> If the paycheck wasn't direct deposit, we'd have to keep a minimum balance or pay $1/month for online bill pay -- still much less than postage stamps to send checks myself.
We don't allow direct debit from our account; that was a personal decision. This way I'm forced to look over the bills and set up the payments. We do have some bills that are the same each month, and I can set up automatic payments to those.
I prefer to pay cash at local small businesses whenever possible -- there's a charge to the business for accepting anything else, including checks and debit cards. I figure an extra couple of percent in the veterinarian's coffers will be well used somehow.
I prefer to have the online bill payment system for big companies, particularly big companies that you don't quite trust. If they try to double bill me, I just fire up the computer, log into the account, and bring up that payment, and ask the bill payer to send them a copy of the transmittal number. I don't have to yell at anyone, get upset or do anything except check a little box and write a short message to the bill pay company. Get an email back about a week later that all is resolved. The once this didn't work (company had accepted payment, applied it to another account, then couldn't figure out whose account was credited, I got hold of the bill payer folks the second time -- I was told that if the company that screwed up couldn't manage to get it right, There Would Be A Conference Call, and if it was still mishandled, Bill Payer would blacklist the company. Didn't get that far, though so I don't know if it was a "wait till your father gets home, young sir!" or a threat with real teeth.
Most of the bill payments are accepted electronically; paper checks are sent by the bill pay company to anyone without electronic funds acceptance.
The CU is currently experimenting with scanning checks at home rather than requiring you to go to an ATM or branch. Many of the CU members are tech workers, and many of them work at home, far from ATMs. I think that will be rolled out further soon.
We can move funds from any account we currently own to any other account we currently own electronically. Again, the CU is thinking about allowing funds to be transferred into any other account at the CU, regardless of whether you own it or not. That will probably require "pseudo-accounts", where if you were going to transfer funds directly to my account, I'd give you an "account number" that actually wasn't my account, but one created by the bank for this purpose specifically -- rather like the pseudo-credit card numbers some credit cards will give you for online use.
We also have some automatic account messaging options; I can have email or text messages sent automatically if an account is low in funds, or a large expenditure goes out, or any of a number of conditions that I set up.
So the long and the short of it is that I rarely write checks. Rarely get any, either.