As I understand it, this relies on the admin account's ability to write to the /Applications folder without a password. So, if you just run in a non-admin account, you should be fine.
If people are willing to click through several steps of an installer app, they'll also type in the admin password if requested.
This is only useful for other family members that you do not trust for safety reasons.
Though, if you're concerned about having to give an admin password (as evidently some people are), running in a non-admin account would solve that. (Also, if you have write privileges to /Applications, it's possible to write a script overwriting the contents of a trusted executable with malicious code, but that isn't how this works so it's slightly irrelevant.)