Ah yes, but there is always that subtle difference between "stealing" hard work and kindly "sharing" hard work. I don't lock my maps because I think that even if it will get stolen, which it probably will, it allows a person to see it and how I did much of it. For one map, I couldn't figure out how to give the neutral units to another player. But then, I looked in one unlocked Turret Defense, was able to copy a trigger, and finished my map.
Personally, I think locking maps is quite frustrating, to say the least. I have seen well made maps that could have used a subtle correction to make them the best maps ever, but I cannot get into them to merely change something such as the amount of upgrades. Take Starship Troopers SE, for instance. Actually, I can get the map by e-mailing the guy, but why go through all that trouble? I have been able to beat that flawlessly each time, due solely to the fact that his anti-medic wall trigger does not cover a large enough location and due to the fact that he has fifty+armor upgrades possible. With 50 armor, you become invincible. The arbitors are pretty cheap too, considering the enemy doesn't have shared vision. I would quickly alter this to make it harder and more fair, which in turn would make it more fun. HOWEVER, the map is LOCKED! So, instead, we get to see these possible treasure troves get lost beneath the endless pile of defenses and bounds. These reasons here should be a good reason to leave a map unlocked or at least release and unlocked version, shouldn't they?
YES people may steal the hard work, but there is also the pride that a person should receive in knowing that THEY might have inspired a person to make a good map because THEY felt it unnecessary to lock their map containing all their time and knowledge. I don't get too mad when a person steals my maps--I figure it will happen. However, I do feel good knowing that occasionally a map maker is out there that is inspired by my ideas and decides to make a different map using many of the triggers I have created. Heck, if I found some odd way to make a new unit that was actually playable over bnet, there is no way that I'd just use this new unit in all of my maps and lock them all. I would want to see my work in other maps, as well.
Just my two cents worth of sense. I believe that map making should be a community of sharing ideas, which includes triggers. Ideas locked away are about a good as using a refrigerator for soccer. Creating triggers can be quite lengthy--it took me about ten hours for a single map of perfectly timed spawn triggers--so why not share them?
Plus, if you un-protect a map, it has to use at least some thought in unprotecting it, so why would we be considered Total Newbies? =P