This is particularly true of gyms, for some reason. In many cases, gym membership agreements have terms requiring the customer to cancel in person, too.
I think it's a public service to tell young people how gyms work. Basically it's high pressure sales ("this discount membership offer only good for today!") plus hard to cancel memberships.
Gyms work on a model of human nature + oversubscription.
Human nature means that a huge % of people join the gym, go two weeks, and never return. Then it's hard to cancel, so the same people that don't bother coming in, don't bother figuring out the membership cancellation gauntlet.
They charge a day fee or a monthly fee or you can pay for 3, 6 or 12 months.
I've never given then any credit card or bank details as I pay cash, but I believe they do offer direct debit.
That seems like it should be explicitly illegal. I suspect it is already technically illegal in many jurisdictions. In the UK I'm pretty sure this would be considered an unfair contract term.
I've tried signing up for gym twice, first time, I gave in to their pressure sales pitch (yeah I was naive) but canceled the contract under WA's RCW 19.142.040 (I have three days to cancel it for any reasons) , second time I walked away after getting tired of pressure sales. They particularly shame you for out of shape, etc, too.
This pretty much this sums up why I absolutely dislike these style of sales...
ACH / Direct Debit payments are much cheaper for the merchant to have rejected. Typically $0.25 or less.