I don't see the connection between a SAFETY and a key lock.
If it took a key to put your Marlin off safe, would you still buy one?
The "connection" jcn59, is that the Marlin, and the later Winchesters did not need a safety, but the lawyers and their lawsuits against guns caused the two companies to put the safety on the rifles. MANY complained about them and how unnecessary they were. It was a SAFETY.
What do YOU think the key lock on the newer Smiths are? How about a SAFETY feature?

I don't use the key lock so it is of no consequence.
Now! If I wanted a Marlin but, it had a key lock on it to answer your question. I most likely would if I "WANTED" the rifle.
To me this whole thing is inconsequential. If you don't lock the gun, the gun is unaffected. Throw the keys down a well, and never worry about them again.
If you don't like Smiths, don't buy them. If you don't like their way of avoiding lawsuits, PAY THEIR LEGAL FEES, or stop voting for the lessor of two evils, and gettin the same damn thing over and over in laws passed, and NRA lobbying compromises. Trail lawyers have been made fabulously wealthy over things like this, and the folks responsible are the Democrat and Republican VOTERS that monotonously continue to put in office THEIR PARTY COMPROMISE, by voting party instead of individual.