The local Lomography retailer that I'm most familiar with had for the longest time a sign above their Lomography display that read "No Photography Allowed".
They are more of a gift or souvenir store than anything else.
Glazer's in Seattle has a good approach. They have Holga and similar equipment in its own area - displayed in a manner similar to other specialty equipment and supplies. They also sponsor contests and otherwise promote to that portion of the market in a way that would be likely to draw customers into their store, where there are many other film based options.
I think people who are interested in Lomography and the like are extremely unlikely to ask users of roll film cameras the classic question "Can you still get film for that?"
The Large format users - they are on their own

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