There was an interesting section in Risk Factors, on pages 39 - 40.

>> Our marketing efforts currently include referrals, affiliate programs, free or discount trials, partnerships, display advertising, television, billboards, radio, video, direct mail, social media, email, podcasts, hiring and classified advertisement websites, mobile “push” communications, search engine optimization, and keyword search campaigns. Our marketing initiatives may become increasingly expensive and generating a meaningful return on these initiatives may be difficult.

I think you implied that marketing is expensive for them and I think you're right. And I think the commodity job that DD does is pretty dangerous since there isn't a lot of brand power to be had. I could be wrong there since I only order delivery once every few months.

True it depends on what their churn looks like and how long it takes to pay back customer acquisition costs.

But if they have some amount of organic growth that is close to or higher than their rate of churn (which is not too crazy an assumption) then they could cut marketing spend and they would grow slower but not start shrinking.