Thanks for the detailed info!It would be unusual for one to fall off, unless it was attached to a wheel surface that was not properly cleaned first.
Ultimately, it depends on if your wheel is flanged or flangless really. A lot of new alloy wheels are flangless on the outside and have a weight flange on the inside.
There are some technical reasons for using them even on flanged wheels in some cases. See an online here that discusses weights in depth. https://www.moderntiredealer.com/article/732663/how-adhesive-weights-are-changing-tire-balancing
Some states (mine included) have actually outlawed the use of lead tire flange weights... so tire companies are moving to the stickies to get past this, though in California here.. they can simply switch to zinc flange weights.
My gen5 has stick-on weights directly from the factory. Probably because these weights work well for automated wheel balancing systems.. which I am sure most factories now days use. They also can be used to "true balance" the wheel before you add a tire to it. Subsequent balancing then only has to deal with any imperfections in the actual tire.