I don't see what you could do about "people browse the site but don't check out." I'm sure that is normal for any website regardless.
Shouldn't it be though? What is the precedent here? Isn't anyone concerned about the slow boiling frog any more?
Honestly it's something that happens with my family quite often. I'll start putting stuff in a cart then someone else changes their mind and we switch to another place to order. And it feels like this happens all the time.