Sugar is, of course, bad for the waistline, not to mention the teeth, but it seems to be perilous for the portfolio, too.

Despite the passion of aficionados like Ms. Estrada and Ms. Burnham, investors took a bath on Crumbs, which abruptly closed down on Monday night, a week after Nasdaq suspended trading of the company’s shares.

And with that, the once widely popular and rapidly expanding cupcake company suffered a slide in fortune reminiscent of the likes of Mrs. Field’s (cookies) and Krispy Kreme (doughnuts) which, if not shut down, have been drastically scaled back.

Connoisseurs could only speculate — would all those frozen yogurt stores be far behind?

Crumbs, which started as a single bakery on the Upper West Side in 2003, seemed to be to the cupcake what Ben & Jerry’s was 25 years earlier to the humble scoop of ice cream. It took a basic beloved dessert and improved it with other sweets to produce a sweet tooth nirvana of flavors. (Ms. Estrada’s favorite of the dozens of Crumbs cupcake offerings was the one that incorporated chocolatey-caramely Samoa Girl Scout cookies.)

Ben & Jerry’s, which began in 1978 as a single scoop shop in Burlington, Vt., survived and thrived, eventually bought by the giant multinational corporation Unilever. Crumbs went public in 2011 and quickly followed a not unfamiliar path for some trendy fast-growing companies in technology and other sectors.