Comment by 9dev
9 hours ago
Every data point you keep can be leaked, or abused, and has to be protected (at least in jurisdictions that don't just go eeh, whatever when it comes to protecting their citizens). There are tons of scenarios where I don't want your IP address, ideally I'd not even like to store your password. The more you store, the more you paint crosshairs on your back for hackers. You need to adhere to regulations, anonymise or delete it as customers leave, and solve problems like "should backups be immutable, or pruned from data I should no longer retain". At a certain size, you even need to defend on the inside to avoid more ruthless managers from abusing data you have been entrusted with for illegal analysis or data sales to analytics companies.
If your view on data protection or privacy is "I don't care about it, my users can go to hell as long as they pay"--then sure, this whole discussion probably seems pointless to you. But otherwise, storing and handling as little data as you can probably resonates with you as a good solution to many problems.
"I don't care about it, my users can go to hell as long as they pay"
The above is also a good reason why you wouldn't want to get any of their data. Users who are not consumers are of no interest, and users who become customers will give the necessary data to make a purchase without any need to spy on them.