"Are there any stores around here?"
Translation:¿Hay alguna tienda por aquí?
I believe that the general rule is: if the expectation is that there are a limited number of stores (bars, banks, or anything else) nearby, then the singular is always used. If, on the other hand, there are a large number or unlimited, or unspecified (but more than one or two) number of things, the plural would be used. https://spanish.kwiziq.com/revision/grammar/using-alguno-alguna-algunos-and-algunas-to-say-some-one-or-any-pronouns
I think the problem comes from the article "a" In English it means at least one. Do you have a house? Yes, I have two. In Spanish "un" means exactly one (and not more). Tienes una casa? NO, tengo dos!! So "Hay una tienda?" literally asks "Is there exactly one store:" (not more), So we use "any" -- "Hay alguna tienda?" --- Are there any stores. It's a little confusing for sure!
Am I wrong to look at this translation this way? I, too, thought the answer should be "tiendas" but after reading the comments, understand that it is just a Spanish way of doing it. I don't fret over it because I think that a Spanish speaker would know what I was saying and not be concerned about correcting my grammer. In other words, I try to remember these idiosyncrasies, but I see no point in demanding an explanation why other than that's just the way it is.
Algunas is positive ningunas is negative. If the sentence is negative in spanish then everything must be negative. That isn't done in english. Positive: ¿Ellos tienen alguna fruta?, Do they have any fruit? Negative: ¿Ellos no tienen ninguna fruta?, Don't they have any fruit?
Hope this helps.
As a rule, Spanish seldom (almost never) uses algunas/algunos to mean "any".
Those words are used to mean "some" or "a few".
If "any" is used in an English sentence, often it is not translated at all in the Spanish version. If it is translated, Spanish uses the singular "algún/ alguna" with a singular noun.