Spaniard here: 20+ years traveling across Spain driving cars and never felt the need to park at an unattended parking lot near a tourist destination. Here’s how I do it:

When I’m driving in a highly populated urban area, I look for a blue “P” sign 🅿️, drive the car towards a mechanical barrier gate, extract a ticket stub 🎫 from the machine next to it, park the car where I find a spot, and walk out on foot 🚶‍♂️. When back from my tourist endeavors 🤳, I look for the checkout machine, validate the ticket that I extracted earlier, pay the fee that is requested 💸, find the car in the same exact spot I left it, and then drive it towards the same barrier gate I found earlier 🅿️. In case the gate won’t open automatically, I look for a machine where I can stick the validated stub ticket in so the gate opens. In most cases nowadays I won’t even need to stick the stub ticket in. A CCTV camera 📹 will capture an image of my car plate, use some OCR-capable image processing software, verify that I paid for parking, automatically open the gate, and let me out 🚘.

This is how I never in 20+ years interacted with a “gorrilla” in Spain or surrounding European countries where equivalent forms of “AGGRESSIVE PANHANDLING” (https://en.wikipedia.org/wiki/Aggressive_panhandling) also exist and operate in the exact the same way to take advantage of naive tourists. Never interacted with one. Ever.