Shopping trip

Ok I like shopping, my name might give it away just a teenie tiny bit. Went in one of my regular shops today. For some reason whenever I'm sitting in the queue the person who comes up behind me will always ask "Are you in the queue?" OK "always" being last 3 times

Which is getting frankly rather annoying,There might be few clues to give it away.....

I'm sitting at the start of the cattle pen that leads to the cash desk
I'm holding something on my lap
Ive got my cash card in the other hand
Bags hanging off back off wheelchair
I don't look like I work there/stock taking/modeling or doing health and safety audit

Now while a simple question shoulnt be so annoying its really winding me up!!
So any tips on how to look more like I'm shopping send them this way!