A 2010 survey conducted by the Central Bureau of Statistics showed that 25.7% of secular Jews in Israel aged 20 and older fast on Yom Kippur. It also showed that the customs most frequently observed among the secular are participation in traditional Passover dinner ceremonies — 81.5% reported celebrating the Seder and 67.3% lighting Hanukkah candles — festive family occasions that are not physically or spiritually difficult, like a day-long fast. 

In another survey, conducted by the Bina Center, leading up to Yom Kippur in 2013, the portion of secular Jews who intended to fast rose to 46.5%, a significant increase.

Indeed, many members of the secular Jewish public in Israel actually choose to fast and visit a synagogue on Yom Kippur. The Israeli news website Mako published a provocative article three years ago, wondering: Is there a point in a secular person fasting on Yom Kippur, when he'll continue sinning the next day? 

When Rona Speisman of Tel Aviv spent the last Yom Kippur in Vietnam, she brought a prayer book with her. "I ate a breakfast meal of Pho soup with meat and fish wrapped in banana leaves," she describes the rather non-kosher meal. In Speisman's opinion, there's no contradiction here. "It's my favorite food," she told Al-Monitor, "On Passover I eat shrimp, but because I refrain from eating leavened foods, they wouldn't be fried in breadcrumbs [which are forbidden only during Passover]." Speisman doesn't apologize for her unique way of observing Jewish customs. For her, "It's meaningful to do what my parents and grandparents did in a little town in Poland. It's powerful. The coming together of family and tradition that accompanies you is what it means to be Jewish in my view. The connection between that and what the state and the establishment consider religion is marginal."