Might as well have been a teaching moment.

"Here's 20 bucks, let's run some ads and see how it impacts your channel"

"Didn't change much? Well, wouldn't you rather spend that money on something else instead?"

Part of teaching kids about the Internet is showing what ads are, the way companies use them and that there's always a reason you're getting shown them

As a kid I wanted some shitty toy and my mom went "well, if that's what you want to spend your allowance on, sure. But I think it's probably not as good as you think", only for me to realize that she was right after I got it