Well, you've kinda hit on the solution yourself. I think most people know this intuitively but just need to get the subject on the table. Which it seems you've done.
Although we label it NRE etc around here, it's an old problem. Most people have a tendency to get over-enthusiastic when they discover some new passion. Whether it's a hobby, a profession, an interest of any type. Then we just need someone to take us by the arm and say............whoaaaaaaaa here a minute. Don't forget the rest of the world around you and the impact your actions can have on a bigger sphere. Because that bigger sphere can collapse on YOU too if you don't maintain it !
It's just a reminder.............take a breath..........slow down some here !
For the majority of people that's enough. When needed - supported by specific examples where their exuberance has caused (or almost) some dangerous problems. Seems you have that example (the parents, the house etc and the gossiping mouth in front of the kids) right in front of you.
Good luck !