St. Petersburg city officials are exploring how to cut down on single-use plastic straws, a commendable effort to make the city even more environmentally minded. But to succeed, City Council members should craft a modest, reasonable restriction that encourages businesses and consumers to change their habits. The worst thing they could do is pass an outright ban on straws, which would correctly be branded as government overreach.City Council member Gina Driscoll, who was elected last year, is leading the effort. In a news conference on Tuesday, Driscoll cited a National Park Service statistic that Americans use 500 million plastic straws every day, millions of which end up in waterways where they threaten the health of ecosystems. Communities like St. Petersburg have a lot invested in keeping the coastline clean, including tourism, seafood and responsible environmental stewardship. The campaign, dubbed No Straws St. Pete, has already drawn the support of some two dozen local hospitality groups as well as sponsorship from Bank of the Ozarks. The enthusiasm is encouraging.But Tuesday’s news conference was something of an echo chamber, with T-shirt-wearing activists cheering every sound bite about saving the planet. When the council meets Thursday sitting as the Health, Energy, Resiliency and Sustainability committee, it must take a wider view and a more careful approach. Banning restaurants and other businesses from providing plastic straws would be going too far. What would be the point, other than symbolism that inconveniences and angers residents, of a ban in St. Petersburg that is not in effect in any surrounding city? It would also do more harm to the cause than good, as customers who reach the end of a drive-through lane realize they absolutely, positively cannot have a straw to stick in their soda. The backlash would be fierce.A far better approach would be an ordinance that prohibits businesses from automatically handing out plastic straws with every drink. Businesses could still stock them, but they’d be kept behind the counter and customers would have to specifically ask for them. St. Petersburg would still be the lone Tampa Bay community that restricts plastic straws, but in a way that retains consumer choice. In fact, some businesses in St. Petersburg such as Pom Pom’s Teahouse & Sandwicheria are already providing straws only by request. Activist-minded customers will no doubt want to reward other shops that get behind the effort voluntarily. That’s the best way to build support — from the bottom up.Mayor Rick Kriseman spoke in support Tuesday of No Straws St. Pete but wisely did not promote an outright ban on single-use plastic straws. Cities have a role to play in combatting climate change and instituting smart environmental policies that can spread to more communities. But they shouldn’t be the lifestyle police. Persuading consumers to change ingrained habits is tricky work — and it can backfire. A gentle nudge that requires customers to ask for a straw instead of getting one strikes a reasonable balance and could make a small difference.