What about employees smart enough to boot a laptop from a thumb drive but not smart enough to disassemble it who just want admin to install some game from a dub

What about employees smart enough to boot a laptop from a thumb drive but not smart enough to disassemble it who just want admin to install some game from a dubious source? What about other scenarios neither you or I can think of right now? The cost of activating bitlocker is so low, I'd do it just in case. Also, I'd argue the stolen bag scenario usually features dilletante attackers.