Just imagine someone taking out a cup of sand they safekept from your store. They wanted it delivered to their house which is 20 miles away. Obviously, the gas prices aren't cheap, so are you going to do this service for them anyway? There are operating costs to every service, and if you think 50 cents is much more valuable to get compared to the fee that you are about to incur, then you may have a few screws loose in your head.
Now imagine they charge you $20 per month for keeping the few grains of sand that fell off your shoes, even though you can't get back your grains of sand.
And that's why you don't leave anything at any third-party service at all, be it 20 cents worth of sand or 2 million. You only use them when you need them, and you don't treat them as your personal safe. They make money off of your deposit anyways and letting them charge you for 'safekeeping' something at their platform is just too much.
People should know this by now
