I have switched to prepaid gift cards instead of giving apps the right to take money from my bank account. No payment information linked to Google- got burned by auto renewal once and never again.
Not paying a debt you legitimately owe doesn’t eliminate the legitimacy of the debt. Most app owners probably won’t take any further action against you because it’s not usually worth the time and money (at least in the US), but they’re entitled to. If they sell your debt to a debt collector, have fun with that. (Tangent: there is usually a certain number of years of inaction after which they can’t go after you for th…
Obviously: read the terms of what you’re signing up for, to check.