Express Lanes at Grocery Stores

I bet the express lane at a supermarket is a deterrent to theft. As a person who lives alone in a small apartment I tend to shop as often as I can stand it to reduce wasted space in my house as well as wasted food. One of those green aspects that I favour most - if it saves you money and helps the environment than why not do it? I'll deal with things of that ilk later one when this blog makes the transition to political; which it never will but I will say I have a slant. If I was writing for a newspaper I would hide it but you are in my sphere of influence. My 'corner' of the bloggosphere if you will. Anyways, there are no express lanes at supermarkets in Japan (suupaa in Japanese). It drives me crazy since everybody takes trains home from work, stops at the suupaa near the station then walks home so essentially the supermarket rush hour is very pronounced (far more than my home country... something I feel I am an expert on with my 5 years of experience at the A&P). So I essentially go in an buy an apple and some sort of bentou and have to wait in line. Which I do, grudgingly.
Now yesterday I was at the suupaa with my girlfriend who is far more law abiding than I am. We spent an hour buying groceries (with about 20 minutes of that being spent in the checkout line). Only to realise we didn't buy some necessary chinese spicy paste thingy for our maaboo (a spicy concotion of meat and tofu to be eaten with rice.... fantastic might I add). All I can think is to go back in and buy it will require another 25 minutes so lets just steal it. She said no. Stealing is wrong blah blah blah. But I certainly would have considered it in that situation especially. We just spent 4000JPY and had to wait a long time in the line. The paste was only 140JPY. Overall they are probably still making a profit off of us.
Now if there was an express line for the second trip through and it would only take 5 minutes to pay I probably would never have thought about stealing it. My process was directly from the time wasted paying for it, not the price.
In conclusion I am willing to bet if you compared supermarkets around the world that have express lines with ones that do not you would likely find that they are not only convenient but reduce the instances of theft. Of course you would have to be quite scientific and remove all the other plausible factors with dummy variables or true variables. (ie time of day peak hour is, demographics of the area, strength of laws, if the store implements cameras, tag alarms, etc, etc, etc).