There’s merit in exposure; sometimes the seeds of a genuine shabbos experience remain in a person and have an influence so some point in their life even if they don’t become frum.
Any improvement is worthwhile. The chofetz chaim supported thw kosher kitchen in an army base, even when he heard that Jewish soldiers were eating treif and then getting a second helping at the kosher kitchen. He said that at least they’ll eat a little less treif – that was enough to justify large investments of time and resources, in an era where food was very valuable.
I’m not a lubavitcher; they take this idea to an extreme, where a person putting on what they believe to be random leather boxes from someone who looks Amish is worthwhile – i disagree. I believe that exposure to yiddishkeit needs to be on a level that a frei person can relate to, such as seeing a shabbos table.