The Crawl. This move is a bit desperate and can cause quite a lot of attention from bystanders.
If your Unwanted Greeter hasn’t seen you but is very close by, you can pretend to look at a can of tomato soup at the lowest shelf and slowly (SLOWLY) crawl out to peek if they’re gone.
When the coast is clear, you slowly stand up, act normal (if possible) and maybe mumble something like ”Those darned lower shelves. We’re not getting any younger, I should sue this shop” (thereby diverting the attention of bystanders from your behaviour to the shelves) and walk off.