Just be very careful with the fresh grass that you select and you will be fine. I live in a subdivision and we do not treat our yard with pesticides, fertilizer and all the junk just the have the greenest lushest lawn that needs to be mowed more often- but our neighbors treat their yard like they have something to prove- they even walk around and HAND WEED anything that the chemicals have not eliminated. And of course they mow in 2 directions ot have a crosshatch pattern on the grass after mowing. In a nutshell they are insane and insane about their lawn. And I won’t feed grass from our yard on the small chance that their chemicals have spread to our yard thru wind or water.
My parents have a huge yard with no close neighbors- and from there I have gotten apple branches and clover (grows as a weed) that I know for sure have not been treated and neighbors are not close enough to affect their lawn. But if you live at an apartment or have a small yard (live in a subdivision, etc) I think you are better safe than sorry.