"if they can make a buck..."; sort of.......a store HAS to make over 30% margin on overall sales to even stay in business. A sale (below margin) on something to get ya in the store means something else is higher, but you are in.......now to get you to buy more than just the sale item(s). Extra staffing. licensing, regulation compliance, etc. for a given department costs 'em more. At some point they can determine it just isnt worth it.
This is why I say, for a place like Walmart, if you can tell the Big Boss that you spent, say, $4000 there last year and most of it was somewhere other than 'Sporting Goods', but a big reason you even came in was because 'Sporting Goods' was there, and the same for a bunch of your friends in the community, it might make an impression.