Again, it’s a filter. You give me card details, that means you seriously want the product and also that you trust me. If i treat you right and give you a great experience you’ll be subscribed for years, purchasing add-ons, and recommending me to your friends. That’s much more valuable for me than skimming 20 bucks a month because you forgot to unsub.
When it’s a big corpo sure they’ll do it cause they don’t give a shit about their customers or even their reputation. I’m honestly not saying it doesn’t happen. But when it’s a no-name with a small online product they can’t afford that shit. If they put a credit card wall it’s most likely because they were getting too many people on the free trial, and were having a hard time telling actual future customers from drive-bys. This solves that.