Because he's a terminator. He kills. Dude tried to make him go through a waiting period. Easier to kill the bastid.
ᴳᵒ ᶠᵘᶜᵏ ʸᵒᵘʳˢᵉˡᶠ

tbh would've been hilarious had he shouted "2nd amendment" before pulling the trigger
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The terminator obviously wasn't a fan of veteran character dude Dick Miller.
You've seen Guy Standeven in something because the man was in everything.

like Samantha Fox
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He
wanted to have some fun, because he was deprived.

The police could still hinder its mission and further damage its programming, the Terminator can shake off small arms fire but is vulnerable to being struck by vehicles and explosives. If the military got involved then they could have destroyed it before it could complete its mission.
Melton1 Wanted for Pedophilia:
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https://m.youtube.com/shorts/Zjxk307CND0

Didn't he retreat to make repairs? I could be wrong, haven't seen it in a while.
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You'd think the T800s wouldn't care about the authorities since their only mission is to kill Sarah and John. Yet the one in part 1 took off after crashing a car and the same with avoiding cops in 2 and 3.
Tell you what…When I send my ex-wife her money…you can lick the stamps.

The gun store clerk had to die because he could have called the police and alerted the authorities to the T800’s presence
Melton1 Wanted for Pedophilia:
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He didn't have the money to pay for them and he wasn't going to wait 15 days for anything, so he figured the best way to keep the guns and shut the guy up would be to simply blow his brains out (and it was a great way to test out one of the guns as well!)

Noooooooooooooobody cares
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