Betta Cups

Had a customer today who wanted to put more fish in with his betta fish. 
Specifically he was pointing to our Black Moor Goldfish.
Which get rather large and need larger tanks.
And bettas are usually kept in smaller tanks. Often only one to two gallons.

So to check I asked the customer how big of a tank he had.
He said ten gallons. 

Which is too small for a goldfish and a betta. 

So I asked him the next important question.

Did he have a heater in his tank? Because the other fish would need warmer water to do well.

He did not.

But was willing to buy one once I reassured him that his betta would be okay in the tank with a heater.

So. 

After showing him the heaters, I think pointed out the Neon Tetras as potentially good fish and went to show him more...and he was like "Nope! I want these ones!" 

So I got him the neons out. 
And while bagging them up, he had wandered over to the bettas in their cups.
And after staring at them for a bit was like "Why don't these have heaters?!" 

....Dude seriously?
That's....that's.....one of the oddest questions I'd been asked really.

Like the betta cups are just that. Cups.

And with at least fifty some odd bettas in my store at a time?
Putting heaters in each individual cup would be laudable. 
Especially considering how quickly we sell through our bettas.
Like I end up replacing almost my entire stock by the week. 

Which means that heaters would get lost broken stolen...etc.

Plus like....we don't have/carry heaters that small.
Putting what we do have into those cups? Yah....would boil the fish probably. :S
Don't want that.

Like if it wasn't a temporary living situation in the store then I would be more likely to be like "yes, the bettas need heat" but in the cups? Not really.

-Sarnic Dirchi