My personal experience is the opposite. There is no control on the produce on grandma's backyard and therefore we have no idea how much chemicals she is using. Probably she doesn't know either. But I'm sure of one thing: she definitely uses chemicals if she wants to eat (or sell) those apples. Chemical-free agriculture is more demanding and the grandma doesn't have an incentive to invest in it. After all, using chemicals is what she learned growing up and therefore is the "traditional" way.

I dont think grandmas are out there using genetically modified crops so they can douse the whole thing in Roundup

The idea that Roundup is the worst pesticide being used is optimistic.

It’s like the GP indicates - I think the concern is more for yield than safety.

My experience as a tourist was that some fruit reeked so strongly of chemicals that I just kept away from it.

Grandmas can be growing it in heavily contaminated soils (old motor oil, lead, arsenic, etc.), or using ‘random weed spray’ at 10x its recommended dosage, or not washing their hands after using the toilet and then handling veggies, etc.

Your scenario provides far fewer applications of pesticides than the alternatives, especially those in "organic farming", with a pesticide that is much less bad than the common alternatives.