Well ,since Dr Keane has not been able to help yet, I'll do what I can.
Let's get one thing aout of the way first. You like to smell shoes that ladies have worn.
It's not illegal, it's not immoral and it's not fattening - so just enjoy it. You are harming nobody, and we all have our secret little sexual delights.
I suspect, to tell you truth, that you migh quite tnjoy the frisson of pleasure or anxiety
you experience when yo make your purchases. Many of my clients say that in fact this is part of the overall experience - and you have nothing to be ashamed of. Mist clerks in stores are only to help people who want to purchase something 'forbidden' - they have seen it all before and are usually sympathetic. If a lady laughed at you buying sme shoes, I expect she was not being unkind, just faintly amused. Perhaps she felt a bit embarassed when she bought her latest vibrator!
Now to get practical - each pair you buy has it's own unique aroma, I suspect, because we all have quite distinctive personal odors. So to preserve those, a large, sealable plastic bag for each pair is required. Simple.
Then just put them all in a box and take your pick when you like. You are not a freak, you are perfectly normal - you just have different preferences. Me - I don't like the odor of worn shoes, either mens or womens, but I do like a beer sometimes, and alcohol causes many more problems than used shoes!