Those crappy Leupold.... Go take a look up and down the line shooting metallic silhouette. A game where in match and practice you shoot quite a lot (especially small bore) and scopes are adjusted many times every match and stability and return to zero and precise adjustments matter a lot. You will find Leupold outnumbers all the other scopes combined. Accuracy/repeatability/stability/weight are the reasons.
Are they perfect? Nope. Are they all I own? Nope. Are still a great value and reliable? Yep. YMMVMD
You are partly correct. Leupold is the standard in silhouette for a few reasons. Weight absolutely is one. When you need to make 8 pounds 8 oz for smallbore Hunter class you can't hang a 2 pound scope on your sporter.
Otherwise, the more or less standard scope is silhouette is the straight 25X with a 3/8 or 1/2 moa dot. Quarter minute clicks. Weighs 15 oz. You don't need more than about 12 MOA adjustment from chickens to rams, smallbore or high power. And typically it's more like 9.
Who other than Leupold makes a scope to fit those parameters? NOBODY. In fact nobody makes one now at all as Leupold discontinued the silhouette scopes last year. But until recently they made the only real silhouette scope on the market.
And FWIW, every year I see Leupolds fail on the silhouette line. And you bet on 22s. They do get shot 5 - 10 000 rounds a year. It seems every year I need to send one back, in fact just got a 6.5-20X40 EFR back from servicing. The parallax knurled ring detached from the actual parallax adjustment, which is a big hassle when you are focusing every tenth shot for the next animal and distance. And the plug on the bottom of the adjustment turret that is used to seal the scope fell out, nothing like seeing into the innards of your nice fogproof scope and putting electical tape over the hole in the middle of a match and hoping it doesn't fog. That scope is less than two years old.
The year before a 1" 8.5-25X40 failed in the middle of a big match. Zeroed at the beginning of the match, it needed several extra minutes up to hit the target from it's zero verified a few minutes earlier.
One thing to consider regarding holding zero and silhouette. Conditions, mostly temperature, changes throughout the day. It's not uncommon to see your zero change a quarter or half minute. As silhouette shooters, we assume it is conditions changing. If it was in fact the scope zero retention wandering a bit, we would never know it.
Does that mean I don't use them? No, my rifles wear three 25Xs and the one 6.5-20EFR which gets used for dry fire practice in the basement all winter. But it's no surprise when one goes wonky in the midst of a match.
I keep on hoping that Sightron will expand on their fixed power target scope lineup with something that has a little less magnification. their 45x45 ED scope is really nice and fairly lightweight. Maybe March will do it as well? Their 2.5-25x42 is not too far off, but it 22ounces, which I think is around 4-5 ounces heavier than Leupold EFR.
With Leupold not paying too much attention to this market and Weaver going the way of the dodo, there aren't too many lightweight target scopes out there for Silhouette.
Go take a look up and down the line shooting metallic silhouette. A game where in match and practice you shoot quite a lot (especially small bore) and scopes are adjusted many times every match and stability and return to zero and precise adjustments matter a lot. You will find Leupold outnumbers all the other scopes combined. Accuracy/repeatability/stability/weight are the reasons. 
