So you're one those guys who slaps or should I say "sticks" with tape, panels on a roof and calls it good? Mine aren't going anywhere. Yes, use what you want to your own and others detriment.
How's it gonna feel when unbeknownst to you, your "right" tape job begins to rightfully work itself loose and panels end up through the windshield of a minivan full of kids or worse, causing multiple vehicles to crash? It happens more often than you're willing to admit, obviously.
There IS only one way to install panels--the safe and secure way. We're not talking about plastic moulding or fiberglass body trim.